ListView點選Item更換顯示內容圖片
阿新 • • 發佈:2019-01-31
先上效果圖
佈局檔案(就是一個listView)
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ListView
android:id ="@+id/lv"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</RelativeLayout>
activity中的程式碼,模擬的假資料設定listView
public class MainActivity extends Activity {
private ListView lv; private ArrayList<String> list; private MyAdapter adapter; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); initLayout(); } private void initLayout() { if(list == null){ list = new ArrayList<>(); } for (int i = 0; i < 20; i++) { list.add("正常顯示....."); } lv = (ListView) findViewById(R.id.lv); adapter = new MyAdapter(list,this); lv.setAdapter(adapter); lv.setOnItemClickListener(new AdapterView.OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { adapter.setCurrentPosition(position); adapter.notifyDataSetChanged(); } }); }
}
設定Adapter,主要的點選和切換事件都在這裡面,這裡是通過動態來添加布局內容的
public class MyAdapter extends BaseAdapter {
int mCurrentPos;
ArrayList<String> list;
Context mContext;
public MyAdapter(ArrayList<String> list,Context context) {
this.list = list;
this.mContext = context;
}
public void setCurrentPosition(int position){
this.mCurrentPos = position;
}
@Override
public int getCount() {
return list.size();
}
@Override
public Object getItem(int position) {
return list.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
LinearLayout layout = new LinearLayout(mContext);
layout.setOrientation(LinearLayout.VERTICAL);
//說明點選的是當前的位置,設定為獲取焦點
if(mCurrentPos == position){
layout.addView(addFocusView());
}else{
layout.addView(addNormalView(position));
}
layout.setGravity(Gravity.CENTER);
return layout;
}
/**
* 獲取焦點的位置
*/
public View addFocusView(){
ImageView iv = new ImageView(mContext);
iv.setLayoutParams(new LinearLayout.LayoutParams(150,150));
iv.setImageResource(R.drawable.focus);
return iv;
}
/**
* 正常情況下listView的內容顯示
*/
public View addNormalView(int position){
LinearLayout layout = new LinearLayout(mContext);
layout.setOrientation(LinearLayout.HORIZONTAL);
ImageView iv = new ImageView(mContext);
iv.setImageResource(R.drawable.nomal);
layout.addView(iv, new LinearLayout.LayoutParams(150,150));
TextView tv = new TextView(mContext);
tv.setText(list.get(position));
tv.setTextSize(30);
layout.addView(tv,new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT));
layout.setGravity(Gravity.CENTER);
return layout;
}
}