Android的异步任务进度条onProgressUpdate [英] Android Async Task Progress Bar onProgressUpdate
问题描述
我是一个新的程序员。我见过很多的教程,但不明白什么是错的。我想创建一个异步任务进度。然而,它总是崩溃我的应用程序。
下面是主的应用程序:
包pt.flag.ensemble;
导入了java.util.Random;
进口pt.flag.ensemble.task.AsyncTaskBar;
进口android.app.Activity;
进口android.content.Context;
进口android.content.Intent;
进口android.content.Shared preferences;
进口android.media.MediaPlayer;
进口android.os.Bundle;
进口android.view.Menu;
进口android.view.MenuItem;
进口android.view.View;
进口android.widget.Button;
进口android.widget.ImageButton;
进口android.widget.ProgressBar;
进口android.widget.Toast;
公共类间隔延伸活动{
私有静态间隔实例;
私人上下文的背景下;
私人字符串的答案;
INT right_question;
INT wrong_question;
INT randomInt2;
公共进度的进度;
@覆盖
保护无效的onCreate(包savedInstanceState){
super.onCreate(savedInstanceState);
的setContentView(R.layout.activity_intervals);
//初始化声音
最后的MediaPlayer Sound1例子= MediaPlayer.create(Intervals.this,
R.raw.maj2);
最后的MediaPlayer SOUND2 = MediaPlayer.create(Intervals.this,
R.raw.maj3);
最后的MediaPlayer sound3 = MediaPlayer.create(Intervals.this,
R.raw.maj4);
//进度条
例如=这一点;
进度进度=(进度)findViewById(R.id.Progressbar);
progressBar.setProgress(0);
//播放方法
最后的ImageButton播放=(的ImageButton)findViewById(R.id.Play);
Play.setOnClickListener(新View.OnClickListener(){
@覆盖
公共无效的onClick(视图查看){
新AsyncTaskBar()执行()。
Play.setEnabled(假);
//生成随机数
随机randomGenerator =新的随机();
INT randomInt = randomGenerator.nextInt(3)+ 1;
randomInt2 = randomInt;
//选择合适的音效播放
开关(randomInt){
情况1:
sound1.start();
回答=M2;
打破;
案例2:
sound2.start();
回答=M3;
打破;
案例3:
sound3.start();
回答=P4;
打破;
}
}
});
//音频重复方法
按钮重复=(按钮)findViewById(R.id.Repeat);
Repeat.setOnClickListener(新View.OnClickListener(){
@覆盖
公共无效的onClick(视图查看){
//选择合适的音效播放
开关(randomInt2){
情况1:
sound1.start();
新AsyncTaskBar()执行()。
回答=M2;
打破;
案例2:
sound2.start();
新AsyncTaskBar()执行()。
回答=M3;
打破;
案例3:
sound3.start();
新AsyncTaskBar()执行()。
回答=P4;
打破;
}
}
});
}
//回答方法
公共无效buttonClicked2(查看视图){
按钮clickedButton =(按钮)视图;
如果(clickedButton.getText()的toString()。等于(答案)){
Toast.makeText(Intervals.this,你说得对!,Toast.LENGTH_LONG)
。显示();
right_question = right_question + 1;
最后的ImageButton播放=(的ImageButton)findViewById(R.id.Play);
Play.setEnabled(真正的);
//通过结果
共享preferences共享preF = getShared preferences(
INTERVALRIGHTS,Context.MODE_PRIVATE);
共享preferences.Editor编辑=共享pref.edit();
editor.putInt(分数,right_question);
editor.commit();
} 其他 {
Toast.makeText(Intervals.this,你错了!,Toast.LENGTH_LONG)
。显示();
wrong_question = wrong_question + 1;
//通过结果
共享preferences共享preF02 = getShared preferences(
INTERVALWRONGS,Context.MODE_PRIVATE);
共享preferences.Editor编辑=共享pref02.edit();
editor.putInt(SCORE02,wrong_question);
editor.commit();
}
}
@覆盖
公共布尔onCreateOptionsMenu(功能菜单){
//充气菜单;这增加了项目操作栏,如果它是present。
。getMenuInflater()膨胀(R.menu.intervals,菜单);
返回true;
}
@覆盖
公共布尔onOptionsItemSelected(菜单项项){
//处理动作栏项目点击这里。将操作栏
//自动在主/向上按钮操作的点击,只要
//你在AndroidManifest.xml中指定一个父活动。
开关(item.getItemId()){
案例R.id.action_settings:
意向意图=新的意图(Intervals.this,IntervalResults.class);
startActivity(意向);
打破;
默认:
返回super.onOptionsItemSelected(项目);
}
返回true;
}
公共静态间隔getApp(){返回实例; }
}
下面是AsyncTask的类
包pt.flag.eventapp.task;
进口pt.flag.eventapp.Main;
进口android.os.AsyncTask;
进口android.os.SystemClock;
进口android.widget.Toast;
公共类ShowDialogAsyncTask扩展的AsyncTask<太虚,整型,太虚> {
INT progress_status;
@覆盖
在preExecute保护无效(){
// TODO自动生成方法存根
super.on preExecute();
//Toast.makeText(Main.getApp(),"Invoke在preExecute(),Toast.LENGTH_SHORT).show();
progress_status = 0;
//Main.getApp().txt_percentage.setText("downloading 0%);
}
@覆盖
保护无效doInBackground(虚空...... PARAMS){
而(progress_status< 100){
progress_status + = 2;
publishProgress(progress_status);
SystemClock.sleep(300);
}
返回null;
}
@覆盖
保护无效onProgressUpdate(整数...值){
super.onProgressUpdate(值);
//Main.getApp().progressBar.setProgress(values[0]);
//Main.getApp().txt_percentage.setText("downloading+值[0] +%);
}
@覆盖
保护无效onPostExecute(无效的结果){
super.onPostExecute(结果);
//Toast.makeText(Main.getApp(),调用onPostExecute(),Toast.LENGTH_SHORT).show();
//Main.getApp().txt_percentage.setText("download完成);
}
}
下面是日志:
08-10 20:38:11.081:E / AndroidRuntime(21441):致命异常:主要
08-10 20:38:11.081:E / AndroidRuntime(21441):显示java.lang.NullPointerException
08-10 20:38:11.081:E / AndroidRuntime(21441):在pt.flag.ensemble.task.AsyncTaskBar.onProgressUpdate(AsyncTaskBar.java:34)
08-10 20:38:11.081:E / AndroidRuntime(21441):在pt.flag.ensemble.task.AsyncTaskBar.onProgressUpdate(AsyncTaskBar.java:1)
08-10 20:38:11.081:E / AndroidRuntime(21441):在android.os.AsyncTask $ InternalHandler.handleMessage(AsyncTask.java:618)
08-10 20:38:11.081:E / AndroidRuntime(21441):在android.os.Handler.dispatchMessage(Handler.java:99)
08-10 20:38:11.081:E / AndroidRuntime(21441):在android.os.Looper.loop(Looper.java:156)
08-10 20:38:11.081:E / AndroidRuntime(21441):在android.app.ActivityThread.main(ActivityThread.java:4977)
08-10 20:38:11.081:E / AndroidRuntime(21441):在java.lang.reflect.Method.invokeNative(本机方法)
08-10 20:38:11.081:E / AndroidRuntime(21441):在java.lang.reflect.Method.invoke(Method.java:511)
08-10 20:38:11.081:E / AndroidRuntime(21441):在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:784)
08-10 20:38:11.081:E / AndroidRuntime(21441):在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
08-10 20:38:11.081:E / AndroidRuntime(21441):在dalvik.system.NativeStart.main(本机方法)
如果我是正确的,日志似乎表明在线路34处的AsyncTask类的错误,这是Intervals.getApp()progressBar.setProgress(数值[0]);。我只是不知道为什么...
此外,这里是我的xml文件
< XML版本=1.0编码=UTF-8&GT?;
< RelativeLayout的的xmlns:机器人=http://schemas.android.com/apk/res/android
机器人:layout_width =FILL_PARENT
机器人:layout_height =FILL_PARENT>
<的ImageButton
机器人:ID =@ + ID /播放
机器人:contentDescription =@字符串/参考hello world
机器人:layout_width =WRAP_CONTENT
机器人:layout_height =WRAP_CONTENT
机器人:SRC =@可绘制/ ic_launcher
机器人:layout_marginTop =50dp
机器人:layout_marginLeft =50dp/>
<按钮
机器人:ID =@ + ID /重复
机器人:contentDescription =@字符串/参考hello world
机器人:layout_width =WRAP_CONTENT
机器人:layout_height =WRAP_CONTENT
机器人:文本=重复
机器人:layout_marginTop =50dp
机器人:layout_toRightOf =@ + ID /播放
机器人:layout_marginLeft =25dp/>
<进度
机器人:ID =@ + ID /进度
风格=@安卓风格/ Widget.ProgressBar.Horizontal
机器人:layout_width =FILL_PARENT
机器人:layout_height =WRAP_CONTENT
机器人:文本=测试
机器人:layout_marginTop =20dp
机器人:layout_below =@ + ID /播放/>
<按钮
机器人:ID =@ + ID / Octave_Button
机器人:layout_width =52dp
机器人:layout_height =80dp
机器人:layout_marginLeft =5DP
机器人:layout_below =@ + ID /进度
机器人:的onClick =buttonClicked2
机器人:layout_marginTop =100dp
机器人:文本=@字符串/八度/>
<按钮
机器人:ID =@ + ID / min2_Button
机器人:layout_width =52dp
机器人:layout_height =80dp
机器人:layout_below =@ + ID /进度
机器人:的onClick =buttonClicked2
机器人:layout_marginTop =100dp
机器人:layout_toRightOf =@ + ID / Octave_Button
机器人:文本=@字符串/ minor2/>
<按钮
机器人:ID =@ + ID / Maj2_Button
机器人:layout_width =52dp
机器人:layout_height =80dp
机器人:layout_below =@ + ID /进度
机器人:的onClick =buttonClicked2
机器人:layout_marginTop =100dp
机器人:layout_toRightOf =@ + ID / min2_Button
机器人:文本=@字符串/ major2/>
<按钮
机器人:ID =@ + ID / min3_Button
机器人:layout_width =52dp
机器人:layout_height =80dp
机器人:layout_below =@ + ID /进度
机器人:的onClick =buttonClicked2
机器人:layout_marginTop =100dp
机器人:layout_toRightOf =@ + ID / Maj2_Button
机器人:文本=@字符串/ minor3/>
<按钮
机器人:ID =@ + ID / Maj3_Button
机器人:layout_width =52dp
机器人:layout_height =80dp
机器人:layout_below =@ + ID /进度
机器人:的onClick =buttonClicked2
机器人:layout_marginTop =100dp
机器人:layout_toRightOf =@ + ID / min3_Button
机器人:文本=@字符串/ major3/>
<按钮
机器人:ID =@ + ID / P4_Button
机器人:layout_width =52dp
机器人:layout_height =80dp
机器人:layout_below =@ + ID /进度
机器人:的onClick =buttonClicked2
机器人:layout_marginTop =100dp
机器人:layout_toRightOf =@ + ID / Maj3_Button
机器人:文本=@字符串/ perfect4/>
<按钮
机器人:ID =@ + ID / A4_Button
机器人:layout_width =52dp
机器人:layout_height =80dp
机器人:layout_below =@ + ID / Octave_Button
机器人:的onClick =buttonClicked2
机器人:layout_marginTop =15dp
机器人:layout_marginLeft =5DP
机器人:文本=@字符串/全音/>
<按钮
机器人:ID =@ + ID / P5_Button
机器人:layout_width =52dp
机器人:layout_height =80dp
机器人:layout_below =@ + ID / min2_Button
机器人:的onClick =buttonClicked2
机器人:layout_marginTop =15dp
机器人:layout_toRightOf =@ + ID / A4_Button
机器人:文本=@字符串/ perfect5/>
<按钮
机器人:ID =@ + ID / minor6_Button
机器人:layout_width =52dp
机器人:layout_height =80dp
机器人:layout_below =@ + ID / Maj2_Button
机器人:的onClick =buttonClicked2
机器人:layout_marginTop =15dp
机器人:layout_toRightOf =@ + ID / P5_Button
机器人:文本=@字符串/ minor6/>
<按钮
机器人:ID =@ + ID / Major6_Button
机器人:layout_width =52dp
机器人:layout_height =80dp
机器人:layout_below =@ + ID / min3_Button
机器人:的onClick =buttonClicked2
机器人:layout_marginTop =15dp
机器人:layout_toRightOf =@ + ID / minor6_Button
机器人:文本=@字符串/ major6/>
<按钮
机器人:ID =@ + ID / minor7_Button
机器人:layout_width =52dp
机器人:layout_height =80dp
机器人:layout_below =@ + ID / Maj3_Button
机器人:的onClick =buttonClicked2
机器人:layout_marginTop =15dp
机器人:layout_toRightOf =@ + ID / Major6_Button
机器人:文本=@字符串/ minor7/>
<按钮
机器人:ID =@ + ID / Major7_Button
机器人:layout_width =52dp
机器人:layout_height =80dp
机器人:layout_below =@ + ID / P4_Button
机器人:的onClick =buttonClicked2
机器人:layout_marginTop =15dp
机器人:layout_toRightOf =@ + ID / minor7_Button
机器人:文本=@字符串/ major7/>
我认为这是更好,如果你通过进度条作为参数传递给的AsyncTask
:
最终进度进度=(进度)findViewById(R.id.Progressbar);
progressBar.setProgress(0);
//播放方法
最后的ImageButton播放=(的ImageButton)findViewById(R.id.Play);
Play.setOnClickListener(新View.OnClickListener(){
@覆盖
公共无效的onClick(视图查看){
AsyncTaskBar任务=新AsyncTaskBar();
task.setProgressBar(进度);
task.execute();
}
然后在你的的AsyncTask
声明 setProgressBar
方法:
公共类ShowDialogAsyncTask扩展的AsyncTask<太虚,整型,太虚> {
进度条;
公共无效setProgressBar(进度条){
this.bar =酒吧;
}
@覆盖
保护无效onProgressUpdate(整数...值){
super.onProgressUpdate(值);
如果(this.bar!= NULL){
bar.setProgress(值[0]);
}
}
您可以使用的TextView
你要设置这样做。
在任何情况下,既然你提到你在这个新的,你可能想看看广播/接收模式。这是怎么一回事呢:
- 启动异步任务,而无需设置进度条或任何东西。
- 定义
的BroadcastReceiver
,实例化一个在你的活动和注册/注销其相应。 - 只要有你的异步任务进度更新只需要调用sendBroadcast的最新进展情况作为一个额外的意向。您可能需要实例化AsyncTask的时候传递一个上下文参数。
- 您的应用程序的广播接收机(你在步骤2中实例化的一个)的onHandleIntent方法将运行在UI线程上,使得所有的UI更新安全。
听起来有点势不可挡?这是第一次,但在这里的好处是:
- 这比通过UI对象的AsyncTask的干净多了。
- 您将了解到一个强大的Android图案会派上用场的其他工作。
- 这会为你节省很多麻烦(和例外情况),如果你切换上下文或您的应用程序内存不足。
I am a new programmer. I have seen lots of tutorials but can't understand what is wrong. I am trying to create a ProgressBar from an Async Task. However it always crashes my application.
Here is the "main" app:
package pt.flag.ensemble;
import java.util.Random;
import pt.flag.ensemble.task.AsyncTaskBar;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.ImageButton;
import android.widget.ProgressBar;
import android.widget.Toast;
public class Intervals extends Activity {
private static Intervals instance;
private Context context;
private String answer;
int right_question;
int wrong_question;
int randomInt2;
public ProgressBar progressBar;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_intervals);
// initializing the sounds
final MediaPlayer sound1 = MediaPlayer.create(Intervals.this,
R.raw.maj2);
final MediaPlayer sound2 = MediaPlayer.create(Intervals.this,
R.raw.maj3);
final MediaPlayer sound3 = MediaPlayer.create(Intervals.this,
R.raw.maj4);
//ProgressBar
instance=this;
ProgressBar progressBar = (ProgressBar) findViewById(R.id.Progressbar);
progressBar.setProgress(0);
// Play Methods
final ImageButton Play = (ImageButton) findViewById(R.id.Play);
Play.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
new AsyncTaskBar().execute();
Play.setEnabled(false);
// generate random number
Random randomGenerator = new Random();
int randomInt = randomGenerator.nextInt(3) + 1;
randomInt2 = randomInt;
// picking the right sound to play
switch (randomInt) {
case 1:
sound1.start();
answer = "M2";
break;
case 2:
sound2.start();
answer = "M3";
break;
case 3:
sound3.start();
answer = "P4";
break;
}
}
});
//Audio Repeat Methods
Button Repeat = (Button) findViewById(R.id.Repeat);
Repeat.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
// picking the right sound to play
switch (randomInt2) {
case 1:
sound1.start();
new AsyncTaskBar().execute();
answer = "M2";
break;
case 2:
sound2.start();
new AsyncTaskBar().execute();
answer = "M3";
break;
case 3:
sound3.start();
new AsyncTaskBar().execute();
answer = "P4";
break;
}
}
});
}
//Answering Methods
public void buttonClicked2(View view) {
Button clickedButton = (Button) view;
if (clickedButton.getText().toString().equals(answer)) {
Toast.makeText(Intervals.this, "You are Right!", Toast.LENGTH_LONG)
.show();
right_question = right_question + 1;
final ImageButton Play = (ImageButton) findViewById(R.id.Play);
Play.setEnabled(true);
// Passing results through
SharedPreferences sharedPref = getSharedPreferences(
"INTERVALRIGHTS", Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putInt("SCORE", right_question);
editor.commit();
} else {
Toast.makeText(Intervals.this, "You are Wrong!", Toast.LENGTH_LONG)
.show();
wrong_question = wrong_question + 1;
// Passing results through
SharedPreferences sharedPref02 = getSharedPreferences(
"INTERVALWRONGS", Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref02.edit();
editor.putInt("SCORE02", wrong_question);
editor.commit();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.intervals, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
switch (item.getItemId()) {
case R.id.action_settings:
Intent intent = new Intent(Intervals.this, IntervalResults.class);
startActivity(intent);
break;
default:
return super.onOptionsItemSelected(item);
}
return true;
}
public static Intervals getApp() { return instance; }
}
Here is the AsyncTask class
package pt.flag.eventapp.task;
import pt.flag.eventapp.Main;
import android.os.AsyncTask;
import android.os.SystemClock;
import android.widget.Toast;
public class ShowDialogAsyncTask extends AsyncTask<Void, Integer, Void> {
int progress_status;
@Override
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
//Toast.makeText(Main.getApp(),"Invoke on PreExecute()", Toast.LENGTH_SHORT).show();
progress_status = 0 ;
//Main.getApp().txt_percentage.setText("downloading 0%");
}
@Override
protected Void doInBackground(Void... params) {
while (progress_status < 100){
progress_status +=2;
publishProgress(progress_status);
SystemClock.sleep(300);
}
return null;
}
@Override
protected void onProgressUpdate(Integer... values) {
super.onProgressUpdate(values);
//Main.getApp().progressBar.setProgress(values[0]);
//Main.getApp().txt_percentage.setText("downloading" + values[0] + "%");
}
@Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
//Toast.makeText(Main.getApp(), "Invoke onPostExecute()", Toast.LENGTH_SHORT).show();
//Main.getApp().txt_percentage.setText("download complete");
}
}
Here is the Log:
08-10 20:38:11.081: E/AndroidRuntime(21441): FATAL EXCEPTION: main
08-10 20:38:11.081: E/AndroidRuntime(21441): java.lang.NullPointerException
08-10 20:38:11.081: E/AndroidRuntime(21441): at pt.flag.ensemble.task.AsyncTaskBar.onProgressUpdate(AsyncTaskBar.java:34)
08-10 20:38:11.081: E/AndroidRuntime(21441): at pt.flag.ensemble.task.AsyncTaskBar.onProgressUpdate(AsyncTaskBar.java:1)
08-10 20:38:11.081: E/AndroidRuntime(21441): at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:618)
08-10 20:38:11.081: E/AndroidRuntime(21441): at android.os.Handler.dispatchMessage(Handler.java:99)
08-10 20:38:11.081: E/AndroidRuntime(21441): at android.os.Looper.loop(Looper.java:156)
08-10 20:38:11.081: E/AndroidRuntime(21441): at android.app.ActivityThread.main(ActivityThread.java:4977)
08-10 20:38:11.081: E/AndroidRuntime(21441): at java.lang.reflect.Method.invokeNative(Native Method)
08-10 20:38:11.081: E/AndroidRuntime(21441): at java.lang.reflect.Method.invoke(Method.java:511)
08-10 20:38:11.081: E/AndroidRuntime(21441): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
08-10 20:38:11.081: E/AndroidRuntime(21441): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
08-10 20:38:11.081: E/AndroidRuntime(21441): at dalvik.system.NativeStart.main(Native Method)
If I am correct, the log seems to indicate an error in line 34 at the AsyncTask class, which is "Intervals.getApp().progressBar.setProgress(values[0]);" I just don't know why...
Also, here is my xml file
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<ImageButton
android:id="@+id/Play"
android:contentDescription="@string/hello_world"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/ic_launcher"
android:layout_marginTop="50dp"
android:layout_marginLeft="50dp" />
<Button
android:id="@+id/Repeat"
android:contentDescription="@string/hello_world"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Repeat"
android:layout_marginTop ="50dp"
android:layout_toRightOf="@+id/Play"
android:layout_marginLeft="25dp" />
<ProgressBar
android:id="@+id/Progressbar"
style="@android:style/Widget.ProgressBar.Horizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="test"
android:layout_marginTop="20dp"
android:layout_below="@+id/Play" />
<Button
android:id="@+id/Octave_Button"
android:layout_width="52dp"
android:layout_height="80dp"
android:layout_marginLeft="5dp"
android:layout_below="@+id/Progressbar"
android:onClick="buttonClicked2"
android:layout_marginTop="100dp"
android:text="@string/octave" />
<Button
android:id="@+id/min2_Button"
android:layout_width="52dp"
android:layout_height="80dp"
android:layout_below="@+id/Progressbar"
android:onClick="buttonClicked2"
android:layout_marginTop="100dp"
android:layout_toRightOf="@+id/Octave_Button"
android:text="@string/minor2" />
<Button
android:id="@+id/Maj2_Button"
android:layout_width="52dp"
android:layout_height="80dp"
android:layout_below="@+id/Progressbar"
android:onClick="buttonClicked2"
android:layout_marginTop="100dp"
android:layout_toRightOf="@+id/min2_Button"
android:text="@string/major2" />
<Button
android:id="@+id/min3_Button"
android:layout_width="52dp"
android:layout_height="80dp"
android:layout_below="@+id/Progressbar"
android:onClick="buttonClicked2"
android:layout_marginTop="100dp"
android:layout_toRightOf="@+id/Maj2_Button"
android:text="@string/minor3" />
<Button
android:id="@+id/Maj3_Button"
android:layout_width="52dp"
android:layout_height="80dp"
android:layout_below="@+id/Progressbar"
android:onClick="buttonClicked2"
android:layout_marginTop="100dp"
android:layout_toRightOf="@+id/min3_Button"
android:text="@string/major3" />
<Button
android:id="@+id/P4_Button"
android:layout_width="52dp"
android:layout_height="80dp"
android:layout_below="@+id/Progressbar"
android:onClick="buttonClicked2"
android:layout_marginTop="100dp"
android:layout_toRightOf="@+id/Maj3_Button"
android:text="@string/perfect4" />
<Button
android:id="@+id/A4_Button"
android:layout_width="52dp"
android:layout_height="80dp"
android:layout_below="@+id/Octave_Button"
android:onClick="buttonClicked2"
android:layout_marginTop="15dp"
android:layout_marginLeft="5dp"
android:text="@string/tritone" />
<Button
android:id="@+id/P5_Button"
android:layout_width="52dp"
android:layout_height="80dp"
android:layout_below="@+id/min2_Button"
android:onClick="buttonClicked2"
android:layout_marginTop="15dp"
android:layout_toRightOf="@+id/A4_Button"
android:text="@string/perfect5" />
<Button
android:id="@+id/minor6_Button"
android:layout_width="52dp"
android:layout_height="80dp"
android:layout_below="@+id/Maj2_Button"
android:onClick="buttonClicked2"
android:layout_marginTop="15dp"
android:layout_toRightOf="@+id/P5_Button"
android:text="@string/minor6" />
<Button
android:id="@+id/Major6_Button"
android:layout_width="52dp"
android:layout_height="80dp"
android:layout_below="@+id/min3_Button"
android:onClick="buttonClicked2"
android:layout_marginTop="15dp"
android:layout_toRightOf="@+id/minor6_Button"
android:text="@string/major6" />
<Button
android:id="@+id/minor7_Button"
android:layout_width="52dp"
android:layout_height="80dp"
android:layout_below="@+id/Maj3_Button"
android:onClick="buttonClicked2"
android:layout_marginTop="15dp"
android:layout_toRightOf="@+id/Major6_Button"
android:text="@string/minor7" />
<Button
android:id="@+id/Major7_Button"
android:layout_width="52dp"
android:layout_height="80dp"
android:layout_below="@+id/P4_Button"
android:onClick="buttonClicked2"
android:layout_marginTop="15dp"
android:layout_toRightOf="@+id/minor7_Button"
android:text="@string/major7" />
I think it's better if you pass the progress bar as an argument to the AsyncTask
:
final ProgressBar progressBar = (ProgressBar) findViewById(R.id.Progressbar);
progressBar.setProgress(0);
// Play Methods
final ImageButton Play = (ImageButton) findViewById(R.id.Play);
Play.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
AsyncTaskBar task = new AsyncTaskBar();
task.setProgressBar(progressBar);
task.execute();
}
And then on your AsyncTask
declare the setProgressBar
method:
public class ShowDialogAsyncTask extends AsyncTask<Void, Integer, Void> {
ProgressBar bar;
public void setProgressBar(ProgressBar bar) {
this.bar = bar;
}
@Override
protected void onProgressUpdate(Integer... values) {
super.onProgressUpdate(values);
if (this.bar != null) {
bar.setProgress(values[0]);
}
}
You could do the same with the TextView
you're trying to set.
In any case, since you mentioned you're new at this you may want to take a look at the Broadcast/Receiver pattern. Here's how it goes:
- Start the async task without setting the progress bar or anything.
- Define a
BroadcastReceiver
, instantiate one in your activity and register/unregister it accordingly. - Whenever there's a progress update on your async task just call sendBroadcast with the progress update as an intent extra. You may need to pass a context parameter when instantiating the AsyncTask.
- The onHandleIntent method of your app's broadcast receiver (the one you instantiated on step 2) will run on the UI thread, making all those UI updates safe.
Sounds a bit overwhelming? It is at first, but here are the benefits:
- It is much cleaner than passing UI objects to an AsyncTask.
- You will learn a powerful Android pattern that will come in handy in other endeavours.
- It will save you a lot of hassle (and exceptions) if you switch context or your app is low on memory.
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