简单的Android拖放不起作用

时间:2017-03-03 21:31:18

标签: android android-layout drag-and-drop imageview android-linearlayout

enter image description here

嗨,正如您在上面的屏幕截图中看到的那样,我有两个linearlayout对象,左侧边栏是一个,而较大的区域,中间的平板电脑图标是另一个。

我想要的是能够将左侧栏上任意2个ImageVies的副本拖到linearlayout对象上。

当我尝试丢弃图像消失时出现问题,我查看了z-index问题,但我不认为这是什么。我很感激任何帮助。

MainActivity.java

注意:我知道我可以创建一个myTouchListener类,而不是每次设置触摸监听器时都实现接口,但为了简单起见没有,因为我是初学的android开发人员。

public class MainActivity extends AppCompatActivity {
ImageView arduinoLogo;
ImageView piLogo;
LinearLayout mainDrop;

String msg;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);


    arduinoLogo = (ImageView) findViewById(R.id.arduinoLogo);
    piLogo = (ImageView) findViewById(R.id.piLogo);
    mainDrop = (LinearLayout) findViewById(R.id.mainDrop);

    mainDrop.setOnDragListener(new View.OnDragListener() {
        @Override
        public boolean onDrag(View v, DragEvent event) {

            switch(event.getAction()){
                case DragEvent.ACTION_DRAG_STARTED:

                    Log.d(msg, "Action is DragEvent.ACTION_DRAG_STARTED");
                    break;
                case DragEvent.ACTION_DRAG_ENTERED:
                    Log.d(msg, "Action is DragEvent.ACTION_DRAG_ENTERED");

                    break;
                case DragEvent.ACTION_DRAG_EXITED:
                    Log.d(msg, "Action is DragEvent.ACTION_DRAG_EXITED");

                    break;
                case DragEvent.ACTION_DRAG_LOCATION  :
                    Log.d(msg, "Action is DragEvent.ACTION_DRAG_LOCATION");

                    break;

                case DragEvent.ACTION_DROP: {
                    View view = (View) event.getLocalState();
                    ViewGroup viewgroup = (ViewGroup) view.getParent();
                    viewgroup.removeView(view);
                    LinearLayout containView = (LinearLayout) v;

                    containView.addView(view);
                    view.setVisibility(View.VISIBLE);

                    break;

                }
                case DragEvent.ACTION_DRAG_ENDED: {
                    Log.d(msg, "Action is DragEvent.ACTION_DRAG_ENDED");
                    break;
                }
                default:
                    break;
            }
            return true;
        }
    });

    arduinoLogo.setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            if(event.getAction() == MotionEvent.ACTION_DOWN) {
                ClipData clipdata = ClipData.newPlainText("", "");
                View.DragShadowBuilder shadowBuilder = new View.DragShadowBuilder(arduinoLogo);
                if (android.os.Build.VERSION.SDK_INT > 23) {
                    v.startDragAndDrop(clipdata, shadowBuilder, arduinoLogo, 0);
                }
                v.setVisibility(View.INVISIBLE);
                return true;
            } else {
                return false;
            }
        }
    });

    piLogo.setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            if(event.getAction() == MotionEvent.ACTION_DOWN) {
                ClipData clipdata = ClipData.newPlainText("", "");
                View.DragShadowBuilder shadowBuilder = new View.DragShadowBuilder(arduinoLogo);
                if (android.os.Build.VERSION.SDK_INT > 23) {
                    v.startDragAndDrop(clipdata, shadowBuilder, arduinoLogo, 0);
                }
                v.setVisibility(View.INVISIBLE);
                return true;
            } else {
                return false;
            }
        }
    });
}

}

activity_main.xml中

<?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:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.proviz.MainActivity">

<LinearLayout
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="horizontal"
    tools:context=".MainActivity"
    android:layout_alignParentTop="true"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true">

    <LinearLayout
        android:id="@+id/mainSidebar"
        android:layout_width="wrap_content"
        android:layout_height="fill_parent"
        android:layout_alignParentLeft="true"

        android:background="#eee"
        android:orientation="horizontal" >
        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:orientation="vertical">
            <ImageView
                android:layout_width="100dp"
                android:layout_height="100dp"
                android:id="@+id/arduinoLogo"
                android:src="@drawable/arduinologo"/>
            <ImageView
                android:layout_width="100dp"
                android:layout_height="100dp"
                android:id="@+id/piLogo"
                android:layout_below="@id/arduinoLogo"
                android:src="@drawable/pilogo"
                android:background="#FFF"
                android:layout_marginTop="1dp"/>
        </LinearLayout>


    </LinearLayout>
    <LinearLayout
        android:id="@+id/mainDrop"
        android:layout_width="match_parent"
        android:layout_height="fill_parent">
        <!--android:background="#00aaaa"-->>
            <ImageView
                android:layout_width="match_parent"
                android:layout_height="100dp"
                android:layout_gravity="center"
                android:src="@drawable/thistablet"/>

    </LinearLayout>

</LinearLayout>

0 个答案:

没有答案