Question

我有两个不同的适配器：一个用于gridView，另一个用于listView。在我的listView中，我有一个用户安装的应用程序列表，旁边有应用程序图标。在每个listView项中，我也有一个复选框。选中此复选框后，我希望它获取该特定应用程序的图标，然后将其发送到gridView，其中图标将出现在gridView中。

问题是当我点击复选框时，我得到了这个NPE：

FATAL EXCEPTION: main
12-22 15:58:45.782: E/AndroidRuntime(28793): java.lang.NullPointerException
12-22 15:58:45.782: E/AndroidRuntime(28793):    at com.example.awesomefilebuilderwidget.AppInfoAdapter$1.onClick(AppInfoAdapter.java:200)
12-22 15:58:45.782: E/AndroidRuntime(28793):    at android.view.View.performClick(View.java:2532)
12-22 15:58:45.782: E/AndroidRuntime(28793):    at android.widget.CompoundButton.performClick(CompoundButton.java:99)
12-22 15:58:45.782: E/AndroidRuntime(28793):    at android.view.View$PerformClick.run(View.java:9308)
12-22 15:58:45.782: E/AndroidRuntime(28793):    at android.os.Handler.handleCallback(Handler.java:587)
12-22 15:58:45.782: E/AndroidRuntime(28793):    at android.os.Handler.dispatchMessage  (Handler.java:92)
12-22 15:58:45.782: E/AndroidRuntime(28793):    at android.os.Looper.loop(Looper.java:150)
12-22 15:58:45.782: E/AndroidRuntime(28793):    at android.app.ActivityThread.main(ActivityThread.java:4333)
12-22 15:58:45.782: E/AndroidRuntime(28793):    at java.lang.reflect.Method.invokeNative(Native Method)
12-22 15:58:45.782: E/AndroidRuntime(28793):    at java.lang.reflect.Method.invoke(Method.java:507)
12-22 15:58:45.782: E/AndroidRuntime(28793):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
12-22 15:58:45.782: E/AndroidRuntime(28793):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
12-22 15:58:45.782: E/AndroidRuntime(28793):    at dalvik.system.NativeStart.main(Native Method)

以下是复选框的onClick方法部分：

addCheckbox
            .setOnClickListener(new View.OnClickListener() {

                @Override
                public void onClick(View v) {
                    if (addCheckbox.isChecked()) {
                        System.out.println("Checked");

                        PackageManager pm = mContext.getPackageManager();
                        final int   DEST_IMAGE_WIDTH = 100;
                        final int DEST_IMAGE_HEIGHT = 100;
                        ApplicationInfo appInfo = mContext.getApplicationInfo();
                        Drawable appIcon = pm.getApplicationIcon(appInfo);
                        Bitmap appBmp  = Bitmap.createBitmap(DEST_IMAGE_WIDTH, DEST_IMAGE_HEIGHT, Config.ARGB_8888); 

                        // Creates a new canvas based on the image specification
                        // created just above.
                        Canvas canvas = new Canvas(appBmp);
                        // (optional) Fills the entire canvas
                        canvas.drawColor(Color.WHITE);
                        // You need to set bounds otherwise a 0,0 sized image would be drawn.
                        appIcon.setBounds(0, 0, DEST_IMAGE_WIDTH, DEST_IMAGE_HEIGHT);
                        appIcon.draw(canvas);

                        /// Let's save to a .jpg file ...
                        File file = new File(mContext.getFilesDir().getAbsolutePath() + "/test2.jpg");
                        FileOutputStream out;
                        try
                        {
                            file.createNewFile();
                            out = new FileOutputStream(file);
                            appBmp.compress(Bitmap.CompressFormat.JPEG, 80, out);
                            Log.i("AppInfoAdapter", "The icon for use in gridView is saved");
                            out.close();

                            // Load back the image file to confirms it works
                          Bitmap bitmap = BitmapFactory.decodeFile( file.getAbsolutePath() );
                          ImageView imageView1 = (ImageView)v.findViewById(R.id.iconImageView_id);
                          imageView1.setImageBitmap( bitmap );  
                          Log.i("AppInfoAdapter", "The icon image has been set into the gridView");
                        }

                        catch (FileNotFoundException e1)
                        {
                            e1.printStackTrace();
                        }
                        catch (IOException e2)
                        {
                            e2.printStackTrace();
                        }


                    } else {
                        System.out.println("Un-Checked");
                    }

                }

这是第200行：

ImageView imageView1 = (ImageView)v.findViewById(R.id.iconImageView_id);

这是我的gridView适配器的getView（）部分，我想将图标图像放入视图中：

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    // Try to reuse the views
    ImageView view = (ImageView) convertView;
    boolean checked = (mCheckBox==null)?false:(((CheckBox)  mCheckBox).isChecked());
    // if convert view is null then create a new instance else reuse it
    if (view == null) {
        view = new ImageView(Context);
        Log.d("GridViewAdapter", "new imageView added");
        view.setId(R.id.iconImageView_id);
    }
    if(checked == true){
        isSdReadable();
        Log.i("GridViewAdapter", "checkbox is checked");

/*FileInputStream in = null;
        try {
            in = Context.openFileInput("BitmapImage");
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        // Load back the image file to confirm it works
        Bitmap bitmap = BitmapFactory.decodeStream(in);
        view.setImageBitmap(bitmap);
        try {
            in.close();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }*/
    } else {
        Log.i("GridView", "Icons not for use/checkbox not checked");
    }

    view.setImageResource(drawables.get(position));
    view.setScaleType(ImageView.ScaleType.CENTER_CROP);
    view.setLayoutParams(new android.widget.GridView.LayoutParams(70, 70));
    view.setTag(String.valueOf(position));
    return view;
}
            });

我试图为新视图分配一个ID，然后在图像中设置（（在我的ONCLICK注意：

ImageView imageView1 = (ImageView)v.findViewById(R.id.iconImageView_id);

在我的网格中：

view.setId(R.id.iconImageView_id);

））但这不起作用，只给我一个NPE，因为两个适配器指向的视图heirachies是不一样的。

那么有没有办法可以让他们指向相同的视图heirachy？（实际上，现在考虑它与我第一次想到这个时相比......

我可以在gridView适配器上使用FileinputStream来获取图像吗？如果是这样，请告诉我如何解决这个问题。我已经尝试过使用OpenfileInput这样的东西，但我无法让它工作。）

增加：

这是listView适配器的整个getView（）：

@Override
public View getView(final int position, View convertView, ViewGroup parent) {
    // get the selected entry
    final ResolveInfo entry = (ResolveInfo) mListAppInfo.get(position);

    // reference to convertView
    View v = convertView;

    // inflate new layout if null
    if (v == null) {
        LayoutInflater inflater = LayoutInflater.from(mContext);
        v = inflater.inflate(R.layout.layout_appinfo, null);
        Log.d("AppInfoAdapter", "New layout inflated");
    }

    // load controls from layout resources
    ImageView ivAppIcon = (ImageView) v.findViewById(R.id.ivIcon);
    TextView tvAppName = (TextView) v.findViewById(R.id.tvName);
    TextView tvPkgName = (TextView) v.findViewById(R.id.tvPack);
    final CheckBox addCheckbox = (CheckBox) v
            .findViewById(R.id.addCheckbox);
    Log.d("AppInfoAdapter", "Controls from layout Resources Loaded");

    // set data to display
    ivAppIcon.setImageDrawable(entry.loadIcon(mPackManager));
    tvAppName.setText(entry.activityInfo.loadLabel(mPackManager));
    tvPkgName.setText(entry.activityInfo.packageName);

    Log.d("AppInfoAdapter", "Data Set To Display");
    addCheckbox
            .setOnClickListener(new View.OnClickListener() {

                @Override
                public void onClick(View v) {
                    if (addCheckbox.isChecked()) {
                        System.out.println("Checked");

                        PackageManager pm = mContext.getPackageManager();
                        final int   DEST_IMAGE_WIDTH = 100;
                        final int DEST_IMAGE_HEIGHT = 100;
                        ApplicationInfo appInfo = mContext.getApplicationInfo();
                        Drawable appIcon = pm.getApplicationIcon(appInfo);
                        Bitmap appBmp  = Bitmap.createBitmap(DEST_IMAGE_WIDTH, DEST_IMAGE_HEIGHT, Config.ARGB_8888); 

                        // Creates a new canvas based on the image specification
                        // created just above.
                        Canvas canvas = new Canvas(appBmp);
                        // (optional) Fills the entire canvas
                        canvas.drawColor(Color.WHITE);
                        // You need to set bounds otherwise a 0,0 sized image would be drawn.
                        appIcon.setBounds(0, 0, DEST_IMAGE_WIDTH, DEST_IMAGE_HEIGHT);
                        appIcon.draw(canvas);

                        /// Let's save to a .jpg file ...
                        File file = new File(mContext.getFilesDir().getAbsolutePath() + "/test2.jpg");
                        FileOutputStream out;
                        try
                        {
                            file.createNewFile();
                            out = new FileOutputStream(file);
                            appBmp.compress(Bitmap.CompressFormat.JPEG, 80, out);
                            Log.i("AppInfoAdapter", "The icon for use in gridView is saved");
                            out.close();

                            // Load back the image file to confirms it works
                          Bitmap bitmap = BitmapFactory.decodeFile( file.getAbsolutePath() );
                          ImageView imageView1 = (ImageView)v.findViewById(R.id.iconImageView_id);
                          imageView1.setImageBitmap( bitmap );  
                          Log.i("AppInfoAdapter", "The icon image has been set into the gridView");
                        }

                        catch (FileNotFoundException e1)
                        {
                            e1.printStackTrace();
                        }
                        catch (IOException e2)
                        {
                            e2.printStackTrace();
                        }


                    } else {
                        System.out.println("Un-Checked");
                    }

                }
            });

    // return view
    return v;
}

增加：新NPE：

02-22 22:56:26.852: E/AndroidRuntime(29276): FATAL EXCEPTION: main
02-22 22:56:26.852: E/AndroidRuntime(29276): java.lang.NullPointerException
02-22 22:56:26.852: E/AndroidRuntime(29276):    at com.example.awesomefilebuilderwidget.AppInfoAdapter$1.onClick(AppInfoAdapter.java:201)
02-22 22:56:26.852: E/AndroidRuntime(29276):    at android.view.View.performClick(View.java:2532)
02-22 22:56:26.852: E/AndroidRuntime(29276):    at android.widget.CompoundButton.performClick(CompoundButton.java:99)
02-22 22:56:26.852: E/AndroidRuntime(29276):    at android.view.View$PerformClick.run(View.java:9308)
02-22 22:56:26.852: E/AndroidRuntime(29276):    at android.os.Handler.handleCallback(Handler.java:587)
02-22 22:56:26.852: E/AndroidRuntime(29276):    at android.os.Handler.dispatchMessage(Handler.java:92)
02-22 22:56:26.852: E/AndroidRuntime(29276):    at android.os.Looper.loop(Looper.java:150)
02-22 22:56:26.852: E/AndroidRuntime(29276):    at android.app.ActivityThread.main(ActivityThread.java:4333)
02-22 22:56:26.852: E/AndroidRuntime(29276):    at java.lang.reflect.Method.invokeNative(Native Method)
02-22 22:56:26.852: E/AndroidRuntime(29276):    at java.lang.reflect.Method.invoke(Method.java:507)
02-22 22:56:26.852: E/AndroidRuntime(29276):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
02-22 22:56:26.852: E/AndroidRuntime(29276):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
02-22 22:56:26.852: E/AndroidRuntime(29276):    at dalvik.system.NativeStart.main(Native Method)

增加2： ids.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
<item type="id" name="iconImageView_id"/>
</resources>

Answer 1

只需将v方法上onClick的名称更改为v1或其他任何内容，

View v = convertView;

和

public void onClick(View v)

在onClick方法中使用v时，您在代码中使用了v CheckBox，但在这种情况下您没有v.findViewById()因为{{ 1}}请参阅v，因此您需要更改其中一个的名称。

//更新

你有新的NPE，就像你在201号线那样，

CheckBox

存在两种可能性：

1-位图为空

2- imageView1为空

首先检查imageView1.setImageBitmap( bitmap );上是否存在iconImageView_id，如果存在则检查位图

//更新2

正如我所见，您尝试将图像从一个适配器添加到另一个适配器，因此您有2个选项。

1 - 在网格适配器上完成这项工作（获取位图）（我不知道你想要什么，但你必须发送一些内容才能获得正确的位图）

2-在layout_appinfo上获取Bitmap的一个列表，然后用GridAdapter填充Grid，并将bitmap ListAdapter添加到该列表并致电gridAdapter.notifyDataSetChanged()要刷新gridAdapter

秒解决方案必须为您服务。

在适配器之间传输图像

1 个答案: