在一個Activity頁面中View跟隨手指移動，並且能實現點擊效果

在一個activity頁面要實現這種效果是很簡單的，最好佈局是RelativeLayout作爲根佈局，然後把一個想要移動的View,比如ImageView，ImageButton,TextView等等放到根佈局下 在這裏的點擊效果並沒有利用onClick,只是通過手指彈起來判斷是否是屬於點擊而已。

佈局

<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.amei.moveviewproject.MainActivity">

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_centerInParent="true"
    android:text="觸摸移動左上角的圖片" />
<ImageView
    android:id="@+id/move_image"
    android:layout_width="80dp"
    android:layout_height="80dp"
    android:src="@mipmap/ic_launcher"
    />

</RelativeLayout>

主頁面MainActivity

public class MainActivity extends AppCompatActivity {

private ImageView moveImage;
private RelativeLayout mRelativeLayout;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    initView();

    moveImage.setOnTouchListener(onTouchListener);
}

private void initView() {
    moveImage = (ImageView) findViewById(R.id.move_image);
    mRelativeLayout = (RelativeLayout) findViewById(R.id.activity_main);
}


/**
 * 是否移動過
 */
private boolean isMove;

private float mLastX;
private float mLastY;
private float mStartX;
private float mStartY;
private long mLastTime ;
private long mCurrentTime;

private View.OnTouchListener onTouchListener = new View.OnTouchListener() {
    int lastX;
    int lastY;
    int left;
    int top;
    int right;
    int bottom;
    int screenWidth;
    int screenHeight;

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        int action = event.getAction();
        switch (action) {
            case MotionEvent.ACTION_DOWN:
                isMove = false;
                lastX = (int) event.getRawX();
                lastY = (int) event.getRawY();
                mStartX = event.getRawX();
                mStartY = event.getRawY();
                mLastTime = System.currentTimeMillis();
                break;
            case MotionEvent.ACTION_MOVE:
                int dx = (int) event.getRawX() - lastX;
                int dy = (int) event.getRawY() - lastY;
                screenWidth = mRelativeLayout.getWidth();
                screenHeight = mRelativeLayout.getHeight();

                if (dx != 0 || dy != 0) {
                    isMove = true;
                }

                left = v.getLeft() + dx;
                top = v.getTop() + dy;
                right = v.getRight() + dx;
                bottom = v.getBottom() + dy;
                if (left < 0) {
                    left = 0;
                    right = left + v.getWidth();
                }
                if (right > screenWidth) {
                    right = screenWidth;
                    left = right - v.getWidth();
                }
                if (top < 0) {
                    top = 0;
                    bottom = top + v.getHeight();
                }
                if (bottom > screenHeight) {
                    bottom = screenHeight;
                    top = bottom - v.getHeight();
                }
                v.layout(left, top, right, bottom);
                lastX = (int) event.getRawX();
                lastY = (int) event.getRawY();
                break;
            case MotionEvent.ACTION_UP:
                if(left <= (screenWidth / 2)) {
                    left = 0;
                }else{
                    left = screenWidth - moveImage.getWidth();
                }
                v.layout(left, top, right, bottom);
                Rect vRect = new Rect();
                v.getHitRect(vRect);
                RelativeLayout.LayoutParams lp = (RelativeLayout.LayoutParams) v
                        .getLayoutParams();
                lp.leftMargin = vRect.left;
                lp.topMargin = vRect.top;
                v.setLayoutParams(lp);

                mLastX = event.getRawX();
                mLastY = event.getRawY();
                mCurrentTime = System.currentTimeMillis();
                if(mCurrentTime - mLastTime < 800){//長按不起作用
                    Log.d("kitchee","開始Y="+mStartY);
                    Log.d("kitchee","最後Y="+mLastY);
                    Log.d("kitchee","移動Y="+Math.abs(mStartY - mLastY));
                    if(Math.abs(mStartX- mLastX )< 10.0 && Math.abs(mStartY - mLastY) < 10.0){//判斷是否屬於點擊
                        Toast.makeText(MainActivity.this,"可以執行點擊任務",Toast.LENGTH_SHORT).show();
                    }
                }
                break;
            default:
                break;
        }
        return true;
    }
};

}