android 实现GridView多选效果
jopen
11年前
在使用 GridView的时候，有时需要多选上面显示的类容，比如批量删除上面显示的图片，批量上传图片等。这个时候我们可以使用层叠图来实现，效果如下，点击图片后，上面会显示出一个打钩的图片，如图：再点击选中图片，勾消失。
具体代码如下：
main.xml
<LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:background="#000000" android:layout_width="fill_parent" android:layout_height="fill_parent" tools:context=".MainActivity"> <GridView android:layout_width="fill_parent" android:layout_height="fill_parent" android:id="@+id/grid" android:verticalSpacing="3dp" android:horizontalSpacing="3dp" android:numColumns="3" ></GridView> </LinearLayout>
item.xml
<?xmlversion="1.0"encoding="utf-8"?> <LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical"> <ImageView android:scaleType="fitXY" android:padding="3dp" android:layout_height="70dp" android:layout_width="70dp" android:id="@+id/image_item" /> </LinearLayout>
package com.imageview; import android.os.Bundle; import android.app.Activity; import android.view.View; import android.widget.AdapterView; import android.widget.GridView; import android.widget.AdapterView.OnItemClickListener; public class MainActivity extends Activity { private Adpter adpter; private GridView gridView; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); int [] image={R.drawable.dog1,R.drawable.m2,R.drawable.m3,R.drawable.m4,R.drawable.m5,R.drawable.dog2}; adpter=new Adpter(image, this); gridView=(GridView) findViewById(R.id.grid); gridView.setAdapter(adpter); gridView.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> arg0, View arg1, int position, long arg3) { adpter.chiceState(position); } }); } } Adpter.java
package com.imageview; import android.content.Context; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.drawable.BitmapDrawable; import android.graphics.drawable.Drawable; import android.graphics.drawable.LayerDrawable; import android.util.Log; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.ImageView; public class Adpter extends BaseAdapter { private int[] image; private boolean isChice[]; private Context context; public Adpter(int[] im, Context context) { this.image = im; Log.i("hck", im.length+"lenght"); isChice=new boolean[im.length]; for (int i = 0; i < im.length; i++) { isChice[i]=false; } this.context = context; } @Override public int getCount() { return image.length; } @Override public Object getItem(int arg0) { return image[arg0]; } @Override public long getItemId(int arg0) { return arg0; } @Override public View getView(int arg0, View arg1, ViewGroup arg2) { View view = arg1; GetView getView=null; if (view == null) { view = LayoutInflater.from(context).inflate(R.layout.item, null); getView = new GetView(); getView.imageView=(ImageView) view.findViewById(R.id.image_item); view.setTag(getView); } else { getView = (GetView) view.getTag(); } getView.imageView.setImageDrawable(getView(arg0)); return view; } static class GetView { ImageView imageView; } //主要就是下面的代码了 private LayerDrawable getView(int post) { Bitmap bitmap = ((BitmapDrawable)context.getResources().getDrawable(image[post])).getBitmap(); Bitmap bitmap2=null; LayerDrawable la=null; if (isChice[post]== true){ bitmap2 = BitmapFactory.decodeResource(context.getResources(), R.drawable.editable_mode_checked_tag); } if (bitmap2!=null) { Drawable[] array = new Drawable[2]; array[0] = new BitmapDrawable(bitmap); array[1] = new BitmapDrawable(bitmap2); la= new LayerDrawable(array); la.setLayerInset(0, 0, 0, 0, 0); //第几张图离各边的间距 la.setLayerInset(1, 0, 65, 65, 0); } else { Drawable[] array = new Drawable[1]; array[0] = new BitmapDrawable(bitmap); la= new LayerDrawable(array); la.setLayerInset(0, 0, 0, 0, 0); } return la; // 返回叠加后的图 } public void chiceState(int post) { isChice[post]=isChice[post]==true?false:true; this.notifyDataSetChanged(); } }</span>