位图图像不能从URL链接显示黑莓 [英] Bitmap Image not displaying from a URL link Blackberry
本文介绍了位图图像不能从URL链接显示黑莓的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
出于某种原因，我的黑莓应用程序崩溃每当我试图从使用互联网的URL显示位图图像。
我找到了 downloadImage（）功能很容易理解，相比于其他计算器上跟随。其他人没有必须就如何落实其功能的例子。我已经测试了功能downloadImage很多次，都失败了。
请给人以code为例说明。谢谢你。
总之，编译器在这一点止于此：
g.drawBitmap（10，Y + 6，50，50，imageBmp，0，0）;
下面是整个code：
包parsepack;进口java.io.ByteArrayOutputStream中;
进口java.io.IOException异常;
进口的java.io.InputStream;
进口java.util.Vector中;进口javax.microedition.io.Connector;
进口javax.microedition.io.HttpConnection;
进口javax.microedition.io.StreamConnection;进口net.rim.device.api.system.Bitmap;
进口net.rim.device.api.system.DeviceInfo;
进口net.rim.device.api.system.Display;
进口net.rim.device.api.system.En codeDIMAGE;
进口net.rim.device.api.ui.DrawStyle;
进口net.rim.device.api.ui.Field;
进口net.rim.device.api.ui.FieldChangeListener;
进口net.rim.device.api.ui.Graphics;
进口net.rim.device.api.ui.Manager;
进口net.rim.device.api.ui.UiApplication;
进口net.rim.device.api.ui.component.BitmapField;
进口net.rim.device.api.ui.component.Dialog;
进口net.rim.device.api.ui.component.LabelField;
进口net.rim.device.api.ui.component.ListField;
进口net.rim.device.api.ui.component.ListFieldCallback;
进口net.rim.device.api.ui.container.MainScreen;
进口net.rim.device.api.ui.container.VerticalFieldManager;
进口net.rim.device.api.xml.parsers.DocumentBuilder;
进口net.rim.device.api.xml.parsers.DocumentBuilderFactory;进口org.w3c.dom.Document中;
进口org.w3c.dom.Node中;
进口org.w3c.dom.NodeList;公共类xmlparsing扩展UIApplication的实现ListFieldCallback，FieldChangeListener
{ 公共静态无效的主要（字串[] args）抛出IOException异常
{
xmlparsing应用=新xmlparsing（）;
app.enterEventDispatcher（）;
}
众长mycolor;
连接_connectionthread;
私有静态ListField _list;
私有静态矢量listElements =新的向量（）;
私有静态矢量listPrice =新的向量（）;
私有静态矢量listAbstract =新的向量（）;
私有静态矢量listIcon =新的向量（）;
私人矢量listInfoVector =新的向量（）;
公共MainScreen屏幕=新MainScreen（）;
位图imageBmp = NULL;
VerticalFieldManager mainManager;
VerticalFieldManager subManager;
UIApplication的UI = UiApplication.getUiApplication（）;
公共xmlparsing（）抛出IOException异常
{
超（）;
pushScreen（屏）; 最后的位图BackgroundBitmap指令= Bitmap.getBitma $ P $的PSource（blackbackground.png）; mainManager =新VerticalFieldManager（Manager.NO_VERTICAL_SCROLL | Manager.NO_VERTICAL_SCROLLBAR）
{ 公共无效漆（图形图像）
{
graphics.drawBitmap（0，0，Display.getWidth（），Display.getHeight（），BackgroundBitmap指令，0，0）; super.paint（图形）;
} }; subManager =新VerticalFieldManager（Manager.VERTICAL_SCROLL | Manager.VERTICAL_SCROLLBAR）
{
保护无效sublayout（INT了maxWidth，诠释了maxHeight）
{
INT displayWidth = Display.getWidth（）;
INT displayHeight = Display.getHeight（）; super.sublayout（displayWidth，displayHeight）;
setExtent（displayWidth，displayHeight）;
}
};
screen.add（mainManager）; _list =新ListField（）
{
公共无效漆（图形图像）
{
graphics.setColor（（INT）mycolor）;
super.paint（图形）;
}
保护布尔navigationClick（INT的地位，诠释时间）
{
尝试
{
//此处导航到另一个屏幕
ui.pushScreen（新ResultScreen（））;
}
赶上（例外五）
{
的System.out.println（异常 - ：navigationClick（）+ e.toString（））;
}
返回true;
}
};
mycolor =至0x00FFFFFF;
_list.invalidate（）;
_list.setEmptyString（*订阅不可*，DrawStyle.HCENTER）;
_list.setRowHeight（70）;
_list.setCallback（本）;
mainManager.add（subManager）;
listElements.removeAllElements（）;
listPrice.removeAllElements（）;
listAbstract.removeAllElements（）;
listIcon.removeAllElements（）;
_connectionthread =新的Connection（）;
_connectionthread.start（）;
}
私有类连接扩展Thread
{
公共连接（）
{
超（）;
} 公共无效的run（）{
文档文档;
康涅狄格州的StreamConnection = NULL;
InputStream为= NULL;
尝试{ 康恩=（的StreamConnection） Connector.open(\"http://imforchange.org/international-movement-for-change/testing/data.xml\"+\";deviceside=true\"); 的DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance（）;
docBuilderFactory.setIgnoringElementContentWhitespace（真）;
docBuilderFactory.setCoalescing（真）;
的DocumentBuilder docBuilder = docBuilderFactory.newDocumentBuilder（）;
docBuilder.isValidating（）;
是= conn.openInputStream（）;
DOC = docBuilder.parse（是）;
doc.getDocumentElement（）正常化（）。
节点列表list1的= doc.getElementsByTagName（eventName的）;
的for（int i = 0; I＆LT; list1.getLength（）;我++）{
节点textNode = list1.item（ⅰ）.getFirstChild（）;
listElements.addElement（textNode.getNodeValue（））; }
节点列表列表2 = doc.getElementsByTagName（eventPrice）;
的for（int i = 0; I＆LT; list2.getLength（）;我++）{
节点textNode = list2.item（ⅰ）.getFirstChild（）;
listPrice.addElement（textNode.getNodeValue（））; } 节点列表项目list3 = doc.getElementsByTagName（eventAbstract）;
的for（int i = 0; I＆LT; list3.getLength（）;我++）{
节点textNode = list3.item（ⅰ）.getFirstChild（）;
listAbstract.addElement（textNode.getNodeValue（））; } 节点列表list4 = doc.getElementsByTagName（eventIcon）;
的for（int i = 0; I＆LT; list4.getLength（）;我++）{
节点textNode = list4.item（ⅰ）.getFirstChild（）;
listIcon.addElement（textNode.getNodeValue（））; } }赶上（例外五）{
的System.out.println（e.toString（））;
} {最后
如果（是！= NULL）{
尝试{is.close（）;
}赶上（IOException异常忽略）{}
}如果（参数conn！= NULL）{
尝试{conn.close（）; }
赶上（IOException异常忽略）{}
}} UiApplication.getUiApplication（）的invokeLater（Runnable的新（）{
公共无效的run（）{
_list.setSize（listElements.size（））;
subManager.add（_list）;
screen.invalidate（）;
}
}）;
}}
公共无效drawListRow（ListField列表，图形克，INT指数，诠释Y，INT W）
{
字符串文本=（字符串）listElements.elementAt（指数）;
串价格=（字符串）listPrice.elementAt（指数）;
字符串textAbstract =（字符串）listAbstract.elementAt（指数）;
INT yPos = 0 + Y;
g.drawLine（0，yPos，W，yPos）;
g.drawText（文字，5，15 + Y，0，w）的;
g.drawText（$+价，5，15 + Y，DrawStyle.RIGHT，W-7）;
g.drawText（textAbstract，5，40 + Y，0，w）的; //图像显示
字符串图片网址=（字符串）listIcon.elementAt（指数）;
imageBmp = downloadImage（图片网址）;
g.drawBitmap（10，Y + 6，50，50，imageBmp，0，0）;
}公共对象获取（ListField名单，INT指数）
{
返回listElements.elementAt（索引）;
}
公众诠释indexOfList（ListField列表，字符串preFIX，INT字符串）
{
返回listElements.indexOf（preFIX，字符串）;
}
公众诠释的get preferredWidth（ListField名单）
{
返回Display.getWidth（）;
}/ *关于关于插入（警告），因为你不使用它的任何地方只是。
*它看起来就像你还说，法允许xmlparsing类外code到
*能够将项目插入列表。也许这就是你想要的，但你只是
*还没有编写其他code使用该方法。我看你至少几个选择有：
* /
公共无效插入（字符串toInsert，INT指数）{
listElements.addElement（toInsert）;
}公共无效fieldChanged（场场，诠释上下文）{
}
公共静态位图downloadImage（字符串URL）
{
InputStream中的IStream = NULL;
恩codeDIMAGE位图;
的HttpConnection的HttpConnection = NULL; 尝试
{
的HttpConnection =（HttpConnection的）Connector.open（URL，Connector.READ_WRITE）; httpConnection.setRequestMethod（HttpConnection.GET）;
INT响应code = httpConnection.getResponse code（）;
如果（响应code == HttpConnection.HTTP_OK）{
的IStream = httpConnection.openInputStream（）;
ByteArrayOutputStream byteArrayOutputStream =新ByteArrayOutputStream（）; 字节[]缓冲区=新的字节[256];
INT LEN = 0，IMAGESIZE = 0; 而（-1！=（LEN = iStream.read（缓冲液）））{
byteArrayOutputStream.write（缓冲液）;
IMAGESIZE + = LEN;
} byteArrayOutputStream.flush（）;
字节[]为imageData = byteArrayOutputStream.toByteArray（）;
byteArrayOutputStream.close（）;
位= EN codedImage.createEn codeDIMAGE（为imageData，0，IMAGESIZE）;
BMP位图= bitmap.getBitmap（）;返回BMP;
}
}
赶上（例外五）
{
}
返回null;
}
}
解决方案
如果您想从WEBURL显示黑莓手机上的画面中的图像。首先，你需要获得一个位图refrence。
您可以检查低于code：
在code将输入作为WEBURL，它会返回一个位图的参考。
进口java.io.DataOutputStream中;
进口java.io.IOException异常;
进口的java.io.InputStream;
进口javax.microedition.io.Connector;
进口javax.microedition.io.HttpConnection;
进口net.rim.device.api.io.IOUtilities;
进口net.rim.device.api.system.Bitmap;
进口net.rim.device.api.system.En codeDIMAGE; 公共类的getImage {
公共静态位图connectServerForImage（字符串URL）{
的HttpConnection的HttpConnection = NULL;
DataOutputStream类httpDataOutput = NULL;
InputStream的httpInput = NULL;
INT RC;
位图bitmp = NULL;
尝试{
的HttpConnection =（HttpConnection的）Connector.open（URL）;
RC = httpConnection.getResponse code（）;
如果（RC！= HttpConnection.HTTP_OK）{
抛出新IOException异常（HTTP响应code：+ RC）;
}
httpInput = httpConnection.openInputStream（）;
InputStream的INP = httpInput;
字节[] B = IOUtilities.streamToBytes（INP）;
恩codeDIMAGE海= EN codedImage.createEn codeDIMAGE（B，0，b.length个）;
返回hai.getBitmap（）;
}赶上（例外前）{
//的System.out.println（URL位图错误........+ ex.getMessage（））;
} {最后
尝试{
如果（httpInput！= NULL）
httpInput.close（）;
如果（httpDataOutput！= NULL）
httpDataOutput.close（）;
如果（HttpConnection的！= NULL）
httpConnection.close（）;
}赶上（例外五）{
e.printStackTrace（）;
}
}
返回bitmp;
}
}
最后，如果你想显示在BlackBerry屏幕上的图像，可以使用下面的方法
g.drawBitmap（XPOS，ypos，W，H，图像，0，0）; //通过位图参照这里
For some reason my blackberry application crashes whenever i try to display a bitmap image from a URL using the internet.
I found the downloadImage() function very easy to understand and to follow compared to others on stackoverflow. The others didnt have any examples on how to implement their function. I have have tested the function downloadImage many times and all failed.
Please give explanation with code example. Thanks.
Anyway, The compiler stops at this point here:
g.drawBitmap(10, y + 6, 50, 50, imageBmp, 0, 0);
Here is the entire code:
package parsepack;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Vector;
import javax.microedition.io.Connector;
import javax.microedition.io.HttpConnection;
import javax.microedition.io.StreamConnection;
import net.rim.device.api.system.Bitmap;
import net.rim.device.api.system.DeviceInfo;
import net.rim.device.api.system.Display;
import net.rim.device.api.system.EncodedImage;
import net.rim.device.api.ui.DrawStyle;
import net.rim.device.api.ui.Field;
import net.rim.device.api.ui.FieldChangeListener;
import net.rim.device.api.ui.Graphics;
import net.rim.device.api.ui.Manager;
import net.rim.device.api.ui.UiApplication;
import net.rim.device.api.ui.component.BitmapField;
import net.rim.device.api.ui.component.Dialog;
import net.rim.device.api.ui.component.LabelField;
import net.rim.device.api.ui.component.ListField;
import net.rim.device.api.ui.component.ListFieldCallback;
import net.rim.device.api.ui.container.MainScreen;
import net.rim.device.api.ui.container.VerticalFieldManager;
import net.rim.device.api.xml.parsers.DocumentBuilder;
import net.rim.device.api.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
public class xmlparsing extends UiApplication implements ListFieldCallback, FieldChangeListener
{
public static void main(String[] args) throws IOException
{
xmlparsing app = new xmlparsing();
app.enterEventDispatcher();
}
public long mycolor ;
Connection _connectionthread;
private static ListField _list;
private static Vector listElements = new Vector();
private static Vector listPrice = new Vector();
private static Vector listAbstract = new Vector();
private static Vector listIcon = new Vector();
private Vector listInfoVector = new Vector();
public MainScreen screen = new MainScreen();
Bitmap imageBmp = null;
VerticalFieldManager mainManager;
VerticalFieldManager subManager;
UiApplication ui = UiApplication.getUiApplication();
public xmlparsing() throws IOException
{
super();
pushScreen(screen);
final Bitmap backgroundBitmap = Bitmap.getBitmapResource("blackbackground.png");
mainManager = new VerticalFieldManager(Manager.NO_VERTICAL_SCROLL | Manager.NO_VERTICAL_SCROLLBAR )
{
public void paint(Graphics graphics)
{
graphics.drawBitmap(0, 0, Display.getWidth(),Display.getHeight(),backgroundBitmap, 0, 0);
super.paint(graphics);
}
};
subManager = new VerticalFieldManager(Manager.VERTICAL_SCROLL | Manager.VERTICAL_SCROLLBAR )
{
protected void sublayout( int maxWidth, int maxHeight )
{
int displayWidth = Display.getWidth();
int displayHeight = Display.getHeight();
super.sublayout( displayWidth, displayHeight);
setExtent( displayWidth, displayHeight);
}
};
screen.add(mainManager);
_list = new ListField()
{
public void paint(Graphics graphics)
{
graphics.setColor((int) mycolor);
super.paint(graphics);
}
protected boolean navigationClick(int status, int time)
{
try
{
//navigate here to another screen
ui.pushScreen(new ResultScreen());
}
catch(Exception e)
{
System.out.println("Exception:- : navigationClick() "+e.toString());
}
return true;
}
};
mycolor = 0x00FFFFFF;
_list.invalidate();
_list.setEmptyString("* Feeds Not Available *", DrawStyle.HCENTER);
_list.setRowHeight(70);
_list.setCallback(this);
mainManager.add(subManager);
listElements.removeAllElements();
listPrice.removeAllElements();
listAbstract.removeAllElements();
listIcon.removeAllElements();
_connectionthread = new Connection();
_connectionthread.start();
}
private class Connection extends Thread
{
public Connection()
{
super();
}
public void run() {
Document doc;
StreamConnection conn = null;
InputStream is = null;
try {
conn = (StreamConnection) Connector.open("http://imforchange.org/international-movement-for-change/testing/data.xml"+";deviceside=true");
DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
docBuilderFactory.setIgnoringElementContentWhitespace(true);
docBuilderFactory.setCoalescing(true);
DocumentBuilder docBuilder = docBuilderFactory.newDocumentBuilder();
docBuilder.isValidating();
is = conn.openInputStream();
doc = docBuilder.parse(is);
doc.getDocumentElement().normalize();
NodeList list1 = doc.getElementsByTagName("eventName");
for (int i = 0; i < list1.getLength(); i++) {
Node textNode = list1.item(i).getFirstChild();
listElements.addElement(textNode.getNodeValue());
}
NodeList list2 = doc.getElementsByTagName("eventPrice");
for (int i = 0; i < list2.getLength(); i++) {
Node textNode = list2.item(i).getFirstChild();
listPrice.addElement(textNode.getNodeValue());
}
NodeList list3 = doc.getElementsByTagName("eventAbstract");
for (int i = 0; i < list3.getLength(); i++) {
Node textNode = list3.item(i).getFirstChild();
listAbstract.addElement(textNode.getNodeValue());
}
NodeList list4 = doc.getElementsByTagName("eventIcon");
for (int i = 0; i < list4.getLength(); i++) {
Node textNode = list4.item(i).getFirstChild();
listIcon.addElement(textNode.getNodeValue());
}
} catch (Exception e) {
System.out.println(e.toString());
} finally {
if (is != null) {
try { is.close();
} catch (IOException ignored) {}
} if (conn != null) {
try { conn.close(); }
catch (IOException ignored) {}
} } UiApplication.getUiApplication().invokeLater(new Runnable() {
public void run() {
_list.setSize(listElements.size());
subManager.add(_list);
screen.invalidate();
}
});
}
}
public void drawListRow(ListField list, Graphics g, int index, int y, int w)
{
String text = (String)listElements.elementAt(index);
String price = (String)listPrice.elementAt(index);
String textAbstract = (String)listAbstract.elementAt(index);
int yPos = 0+y;
g.drawLine(0, yPos, w, yPos);
g.drawText(text, 5, 15+y, 0, w);
g.drawText("$"+price, 5, 15+y, DrawStyle.RIGHT, w-7);
g.drawText(textAbstract, 5, 40+y, 0, w);
// image to display
String imageUrl = (String)listIcon.elementAt(index);
imageBmp = downloadImage(imageUrl);
g.drawBitmap(10, y + 6, 50, 50, imageBmp, 0, 0);
}
public Object get(ListField list, int index)
{
return listElements.elementAt(index);
}
public int indexOfList(ListField list, String prefix, int string)
{
return listElements.indexOf(prefix, string);
}
public int getPreferredWidth(ListField list)
{
return Display.getWidth();
}
/*Regarding the warning about insert(), that's just because you're not using it anywhere.
* It look like you've added that method to allow code outside the xmlparsing class to
* be able to insert items into the list. Maybe that's what you want, but you just
* haven't yet written the other code to use that method. I see you having at least a few choices:
*/
public void insert(String toInsert, int index) {
listElements.addElement(toInsert);
}
public void fieldChanged(Field field, int context) {
}
public static Bitmap downloadImage(String url)
{
InputStream iStream = null;
EncodedImage bitmap;
HttpConnection httpConnection = null;
try
{
httpConnection = (HttpConnection) Connector.open(url, Connector.READ_WRITE);
httpConnection.setRequestMethod(HttpConnection.GET);
int responseCode = httpConnection.getResponseCode();
if (responseCode == HttpConnection.HTTP_OK) {
iStream = httpConnection.openInputStream();
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
byte[] buffer = new byte[256];
int len = 0, imageSize = 0;
while (-1 != (len = iStream.read(buffer))) {
byteArrayOutputStream.write(buffer);
imageSize += len;
}
byteArrayOutputStream.flush();
byte[] imageData = byteArrayOutputStream.toByteArray();
byteArrayOutputStream.close();
bitmap = EncodedImage.createEncodedImage(imageData, 0, imageSize);
Bitmap bmp = bitmap.getBitmap();
return bmp;
}
}
catch (Exception e)
{
}
return null;
}
}
解决方案
If you want to Display an Image on BlackBerry Screen from a WebURL. First you need to get a BitMap refrence.
You can Check the below Code:
The Code will take input as WebURL and It will return a Bitmap reference.
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import javax.microedition.io.Connector;
import javax.microedition.io.HttpConnection;
import net.rim.device.api.io.IOUtilities;
import net.rim.device.api.system.Bitmap;
import net.rim.device.api.system.EncodedImage;
public class GetImage {
public static Bitmap connectServerForImage(String url) {
HttpConnection httpConnection = null;
DataOutputStream httpDataOutput = null;
InputStream httpInput = null;
int rc;
Bitmap bitmp = null;
try {
httpConnection = (HttpConnection) Connector.open(url);
rc = httpConnection.getResponseCode();
if (rc != HttpConnection.HTTP_OK) {
throw new IOException("HTTP response code: " + rc);
}
httpInput = httpConnection.openInputStream();
InputStream inp = httpInput;
byte[] b = IOUtilities.streamToBytes(inp);
EncodedImage hai = EncodedImage.createEncodedImage(b, 0, b.length);
return hai.getBitmap();
} catch (Exception ex) {
// System.out.println("URL Bitmap Error........" + ex.getMessage());
} finally {
try {
if (httpInput != null)
httpInput.close();
if (httpDataOutput != null)
httpDataOutput.close();
if (httpConnection != null)
httpConnection.close();
} catch (Exception e) {
e.printStackTrace();
}
}
return bitmp;
}
}
And Finally,If you want to Display the Image on BlackBerry Screen, use the below method
g.drawBitmap(xpos, ypos, w, h, image, 0, 0);//pass the Bitmap reference Here
这篇关于位图图像不能从URL链接显示黑莓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！
查看全文
