Question

活动代码：

  public void iconSelector(View view) {
    CoordinatorLayout coordinatorLayout = (CoordinatorLayout) findViewById(R.id.create_coordinator);
    LayoutInflater inflater = getLayoutInflater();
    View dialogView = inflater.inflate(R.layout.item_icon_grid_layout, coordinatorLayout, false);


    GridView gridView = (GridView) dialogView.findViewById(R.id.itemIconGridLayout);
    database = new Database(this);
    mId = database.getLastIdOD();
    if(mId>=1) {
        iconList = database.getIconList();

    }
    database.close();
    gridView.setAdapter(new IconsAdapter(getApplicationContext(),iconList));
    gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> parent, View view,
                                int position, long id) {
            mIcon = iconList.get(position).getName();
        }
    });

    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setView(dialogView);
    builder.setTitle(R.string.iconChoose);
    mIconSelectorDialog= builder.show();
}

IconsAdapter中的代码：

    public class IconsAdapter extends BaseAdapter {
  private Context mContext;
List<Icon> iconList;

public IconsAdapter(Context context,List<Icon> list ){
    mContext = context;
    iconList = list;
    int d = iconList.size();
    String i= ""+d;
    Log.d("MyLogIconAdapter",iconList.get(0).getName());
    Log.d("MyLog",i);
}

public int getCount() {
    return iconList.size();

}

public Object getItem(int position) {
    return iconList.get(position).getId();
}

public long getItemId(int position) {
    return position;
}


@Override
public View getView(int position, View convertView, ViewGroup parent) {
    // TODO Auto-generated method stub

    View grid;
    LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    if (convertView == null) {
        grid = new View(mContext);
        grid = inflater.inflate(R.layout.item_icon_grid,null);
        ImageView imageView = (ImageView) grid.findViewById(R.id.imageItemIconGrid);
        int iconResId = mContext.getResources().getIdentifier(iconList.get(position).getName(), "drawable", mContext.getPackageName());
        imageView.setImageResource(iconResId);
    } else {
        grid = (View) convertView;
    }


    return grid;
}

}

Item_icon_grid：

<ImageView
    android:id="@+id/imageItemIconGrid"
    android:src="@drawable/ic_drafts_white_24dp"
    android:layout_width="18dp"
    android:layout_height="18dp"
    android:layout_gravity="center" />

item_icon_grid_layout：

<GridView
    android:id="@+id/itemIconGridLayout"
    android:numColumns="auto_fit"
    android:background="#ffffff"
    android:verticalSpacing="5dp"
    android:horizontalSpacing="5dp"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
</GridView>

日志：

致命的例外：主要处理：com.universe.time.officereminder，PID：25213 java.lang.NullPointerException：尝试调用虚方法＆＃39; void android.widget.ImageView.setImageResource（INT）＆＃39;在null对象上参考在 com.universe.time.proffesionaldiary.adapters.IconsAdapter.getView（IconsAdapter.java:60）在android.widget.AbsListView.obtainView（AbsListView.java:2828）在android.widget.GridView.onMeasure（GridView.java:1064）在android.view.View.measure（View.java:18647）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:5832）在 android.widget.LinearLayout.measureChildBeforeLayout（LinearLayout.java:1435）在android.widget.LinearLayout.measureVertical（LinearLayout.java:721）在android.widget.LinearLayout.onMeasure（LinearLayout.java:612）在android.view.View.measure（View.java:18647）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:5832）在android.widget.FrameLayout.onMeasure（FrameLayout.java:430）在android.view.View.measure（View.java:18647）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:5832）在android.widget.FrameLayout.onMeasure（FrameLayout.java:430）在android.view.View.measure（View.java:18647）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:5832）在 android.widget.LinearLayout.measureChildBeforeLayout（LinearLayout.java:1435）在android.widget.LinearLayout.measureVertical（LinearLayout.java:721）在android.widget.LinearLayout.onMeasure（LinearLayout.java:612）在android.view.View.measure（View.java:18647）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:5832）在android.widget.FrameLayout.onMeasure（FrameLayout.java:430）在 android.support.v7.widget.ContentFrameLayout.onMeasure（ContentFrameLayout.java:135）在android.view.View.measure（View.java:18647）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:5832）在android.widget.FrameLayout.onMeasure（FrameLayout.java:430）在android.view.View.measure（View.java:18647）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:5832）在android.widget.FrameLayout.onMeasure（FrameLayout.java:430）在android.view.View.measure（View.java:18647）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:5832）在 android.widget.LinearLayout.measureChildBeforeLayout（LinearLayout.java:1435）在android.widget.LinearLayout.measureVertical（LinearLayout.java:721）在android.widget.LinearLayout.onMeasure（LinearLayout.java:612）在android.view.View.measure（View.java:18647）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:5832）在android.widget.FrameLayout.onMeasure（FrameLayout.java:430）在 com.android.internal.policy.impl.PhoneWindow $ DecorView.onMeasure（PhoneWindow.java:3012）在android.view.View.measure（View.java:18647）在android.view.ViewRootImpl.performMeasure（ViewRootImpl.java:2298）在android.view.ViewRootImpl.measureHierarchy（ViewRootImpl.java:1320）在android.view.ViewRootImpl.performTraversals（ViewRootImpl.java:1588）在android.view.ViewRootImpl.doTraversal（ViewRootImpl.java:1230）在 android.view.ViewRootImpl $ TraversalRunnable.run（ViewRootImpl.java:6748）在 android.view.Choreographer $ CallbackRecord.run（Choreographer.java:777）在android.view.Choreographer.doCallbacks（Choreographer.java:590）在android.view.Choreographer.doFrame（Choreographer.java:560）在 android.view.Choreographer $ FrameDisplayEventReceiver.run（Choreographer.java:763）在android.os.Handler.handleCallback（Handler.java:739）在android.os.Handler.dispatchMessage（Handler.java:95）在android.os.Looper.loop（Looper.java:145）在android.app.ActivityThread.main（ActivityThread.java:6126） at java.lang.reflect.Method.invoke（Native Method）在java.lang.reflect.Method.invoke（Method.java:372）在 com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:1399）在com.android.internal.os.ZygoteInit.main（ZygoteInit.java:1194）

Answer 1

您可以尝试以下代码，它可能会有所帮助。

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        // TODO Auto-generated method stub

        View grid = inflater.inflate(R.layout.item_icon_grid, null);

        if (convertView == null) {
            ImageView imageView = (ImageView) grid.findViewById(R.id.imageItemIconGrid);
            int iconResId = mContext.getResources().getIdentifier(iconList.get(position).getName(), "drawable", mContext.getPackageName());
            imageView.setImageResource(iconResId);
        } else {
            grid = (View) convertView;
        }
        return grid;
    }

参考：https://www.caveofprogramming.com/guest-posts/custom-gridview-with-imageview-and-textview-in-android.html

Answer 2

错误清楚地表明您正试图在null图片视图中设置图片，因此请检查

ImageView imageView = (ImageView) grid.findViewById(R.id.imageItemIconGrid);

如果是，则图像视图是gridlayout的一部分，而不是检查网格布局的ID和图像视图是否正确。

请调试并检查。

Gridview的Alertdialog（Imageadpater）

2 个答案: