如何在Android上的LinearLayout中实现拖动TextView

时间:2013-04-03 06:26:52

标签: android

下面是我的layout.xml:

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingLeft="30dp" >

    <LinearLayout
        android:id="@+id/ll1"
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        android:orientation="vertical" >

        <TextView
            android:id="@+id/tv1"
            android:layout_width="100dp"
            android:layout_height="wrap_content"
            android:text="Medium Text"
            android:background="#000000"
            android:singleLine="true"      
            android:textAppearance="?android:attr/textAppearanceMedium" />

    </LinearLayout>

</LinearLayout>

我想让TeextView tv1只能在LinearLayout ll1中水平拖动 我实现如下:

ll1 = (LinearLayout)findViewById(R.id.ll1);
tv1 = (TextView)findViewById(R.id.tv1);

Rect rectf = new Rect();
ll1.getGlobalVisibleRect(rectf);
LayoutLeft = rectf.left;

tv1.setOnTouchListener(new OnTouchListener() {
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        float TouchX = event.getX();
        System.out.println("TouchX " + TouchX);
        switch(event.getAction()) {
        case MotionEvent.ACTION_MOVE:
            if(TouchX < LayoutLeft) {
                ll1.setPadding(0, 0, 0, 0);
            }
            else if(TouchX > (LayoutLeft + 100)) {
                ll1.setPadding(100, 0, 0, 0);
            }
            else {
                ll1.setPadding((int)(TouchX - LayoutLeft), 0, 0, 0);
            }
            break;
        case MotionEvent.ACTION_UP:
            break;
        case MotionEvent.ACTION_DOWN:
            break;
        }
        return true;
    }
});

但是我从左到右测试拖动,我得到如下的TouchX值:

04-03 14:24:18.061: I/System.out(18468): TouchX 43.554024
04-03 14:24:18.631: I/System.out(18468): TouchX 92.101845
04-03 14:24:19.731: I/System.out(18468): TouchX 49.150528
04-03 14:24:20.371: I/System.out(18468): TouchX 100.82299
04-03 14:24:22.311: I/System.out(18468): TouchX 54.747032
04-03 14:24:22.781: I/System.out(18468): TouchX 74.458405
04-03 14:24:22.801: I/System.out(18468): TouchX 6.1168213
04-03 14:24:22.821: I/System.out(18468): TouchX 80.44317
04-03 14:24:22.851: I/System.out(18468): TouchX 21.571915
04-03 14:24:22.881: I/System.out(18468): TouchX 89.24452

为什么TouchX值不按顺序?
我怎么修改它?

1 个答案:

答案 0 :(得分:1)

ll1是一个线性布局,我猜你在你的布局中有你的textview。如果将填充设置为linearlayout,则视图中的子项也将添加填充。您必须为linearlayout或textview提供触摸事件。您也可以更改边距而不是textview。找到我的问题解决方案

ll1 = (LinearLayout)findViewById(R.id.ll1);
tv1 = (TextView)findViewById(R.id.tv1);

LinearLayout.LayoutParams layout_param= new LinearLayout.LayoutParams(
                LinearLayout.LayoutParams.fill_parent,
                height * 2);
/or whatever you want to be margins for
layout_param.setMargins(30, 20, 30, 0);


Rect rectf = new Rect();
ll1.getGlobalVisibleRect(rectf);
LayoutLeft = rectf.left;

ll1.setOnTouchListener(new OnTouchListener() {
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        float TouchX = event.getX();
        System.out.println("TouchX " + TouchX);
        switch(event.getAction()) {
        case MotionEvent.ACTION_MOVE:
            //ALTER your layoutparams as per your need. 
            //do calculations on your layout param
            if(TouchX < LayoutLeft) {
                ll1.setLayoutParams(layout_param); 
            }
            else if(TouchX > (LayoutLeft + 100)) {
                ll1.setLayoutParams(layout_param); 
            }
            else {
                ll1.setLayoutParams(layout_param); 
            }
            break;
        case MotionEvent.ACTION_UP:
            break;
        case MotionEvent.ACTION_DOWN:
            break;
        }
        return true;
    }
});

希望这能解决您的问题。