数学与来自一个EditText得到的整数 [英] Math with an integer obtained from an EditText
问题描述
我不知道我做错了,但我有一个名为输入一个EditText,用户写了一个数字,然后你preSS的按钮:
输入=(EditText上)findViewById(R.id.input); XX =(按钮)findViewById(R.id.XX);
XX.setOnClickListener(新View.OnClickListener(){
@覆盖
公共无效的onClick(查看为arg0){ 如果(XX.equals(XX))
{
字符串AA =将String.valueOf(输入);
浮点运算=((浮点)(0.029 * 2.2 * AA));
串卡德纳=将String.valueOf(操作);//设置文本卡德纳(操作的结果)
preDIC =(的TextView)findViewById(R.id. preDIC);
predic.setText(卡德纳); }
问题是,我不能执行此操作。
浮点运算=((浮点)(0.029 * 2.2 * AA));
,因为它强调AA,并说
算子*不能被应用到双,java.lang.String中'
我想,他认为AA是一个字符串,我怎么能使其被理解为一种诠释?
LOGCAT1
09-07 23:18:07.915 10148-10148 / com.example.XXXE / AndroidRuntime:致命异常:主要
java.lang.NumberFormatException:无法解析android.widget.EditText@405a8b98'作为整数
在java.lang.Integer.parse(Integer.java:383)
在java.lang.Integer.parseInt(Integer.java:372)
在java.lang.Integer.parseInt(Integer.java:332) ***在com.example.XXX.XXX $ 5.onClick(XXX.java:542)***崩溃
在android.view.View.performClick(View.java:2506)
在android.view.View $ PerformClick.run(View.java:9112)
在android.os.Handler.handleCallback(Handler.java:587)
在android.os.Handler.dispatchMessage(Handler.java:92)
在android.os.Looper.loop(Looper.java:130)
在android.app.ActivityThread.main(ActivityThread.java:3835)
在java.lang.reflect.Method.invokeNative(本机方法)
在java.lang.reflect.Method.invoke(Method.java:507)
在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:864)
在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:622)
在dalvik.system.NativeStart.main(本机方法)
09-07 23:18:07.965 3698-17447 / system_process W / ActivityManager:
力整理活动com.example.XXXX / .XXXX
您需要修改:
字符串AA =将String.valueOf(输入);
要
内部AA =的Integer.parseInt(input.getText()的toString());
只要你确信该用户将只能进入整数
I don't know what I am doing wrong but I have an edittext called input, where the user writes a number, then you press a button:
input = (EditText) findViewById(R.id.input);
XX= (Button) findViewById(R.id.XX);
XX.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View arg0) {
if(XX.equals("XX"))
{
String aa= String.valueOf(input) ;
float operation= ((float) ( 0.029 * 2.2 *aa ) );
String cadena= String.valueOf(operation) ;
// set text to cadena (result of the operation)
predic = (TextView) findViewById(R.id.predic);
predic.setText(cadena);
}
the problem is that I can't perform this operation
float operation= ((float) ( 0.029 * 2.2 *aa ) );
because it underlines "aa" and says
"Operator '*'cannot be applied to 'double', 'java.lang.String' "
I suppose that he thinks that aa is an String, how can I make it to be read as an Int?
LOGCAT1
09-07 23:18:07.915 10148-10148/com.example.XXXE/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.NumberFormatException: unable to parse 'android.widget.EditText@405a8b98' as integer
at java.lang.Integer.parse(Integer.java:383)
at java.lang.Integer.parseInt(Integer.java:372)
at java.lang.Integer.parseInt(Integer.java:332)
***at com.example.XXX.XXX$5.onClick(XXX.java:542)*** CRASHES
at android.view.View.performClick(View.java:2506)
at android.view.View$PerformClick.run(View.java:9112)
at android.os.Handler.handleCallback(Handler.java:587)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:130)
at android.app.ActivityThread.main(ActivityThread.java:3835)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:507)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:864)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:622)
at dalvik.system.NativeStart.main(Native Method)
09-07 23:18:07.965 3698-17447/system_process W/ActivityManager﹕
Force finishing activity com.example.XXXX/.XXXX
You need to change:
String aa= String.valueOf(input) ;
To
Int aa = Integer.parseInt(input.getText().toString());
As long as you are sure that the user will only be entering integers
这篇关于数学与来自一个EditText得到的整数的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!