我有一个线性布局,我想显示或隐藏与动画,推动布局向上或向下每当我改变其可见性。

我在那里看过一些样品,但没有一个适合我的需要。

我已经为动画创建了两个xml文件,但我不知道当我改变线性布局的可见性时如何启动它们。


当前回答

我在理解和应用公认的答案时遇到了困难。我需要更多的背景知识。现在我已经搞清楚了,下面是一个完整的例子:

MainActivity.java

public class MainActivity extends AppCompatActivity {

    Button myButton;
    View myView;
    boolean isUp;

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

        myView = findViewById(R.id.my_view);
        myButton = findViewById(R.id.my_button);

        // initialize as invisible (could also do in xml)
        myView.setVisibility(View.INVISIBLE);
        myButton.setText("Slide up");
        isUp = false;
    }

    // slide the view from below itself to the current position
    public void slideUp(View view){
        view.setVisibility(View.VISIBLE);
        TranslateAnimation animate = new TranslateAnimation(
                0,                 // fromXDelta
                0,                 // toXDelta
                view.getHeight(),  // fromYDelta
                0);                // toYDelta
        animate.setDuration(500);
        animate.setFillAfter(true);
        view.startAnimation(animate);
    }

    // slide the view from its current position to below itself
    public void slideDown(View view){
        TranslateAnimation animate = new TranslateAnimation(
                0,                 // fromXDelta
                0,                 // toXDelta
                0,                 // fromYDelta
                view.getHeight()); // toYDelta
        animate.setDuration(500);
        animate.setFillAfter(true);
        view.startAnimation(animate);
    }

    public void onSlideViewButtonClick(View view) {
        if (isUp) {
            slideDown(myView);
            myButton.setText("Slide up");
        } else {
            slideUp(myView);
            myButton.setText("Slide down");
        }
        isUp = !isUp;
    }
}

activity_mail.xml

<?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"
    tools:context="com.example.slideview.MainActivity">

    <Button
        android:id="@+id/my_button"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="100dp"
        android:onClick="onSlideViewButtonClick"
        android:layout_width="150dp"
        android:layout_height="wrap_content"/>

    <LinearLayout
        android:id="@+id/my_view"
        android:background="#a6e1aa"
        android:orientation="vertical"
        android:layout_alignParentBottom="true"
        android:layout_width="match_parent"
        android:layout_height="200dp">

    </LinearLayout>

</RelativeLayout>

笔记

感谢这篇文章为我指明了正确的方向。它比本页上的其他答案更有帮助。 如果你想从屏幕上的视图开始,那么不要将它初始化为INVISIBLE。 因为我们是完全在屏幕外制作动画,所以没有必要将它设置为INVISIBLE。如果你的动画不是完全脱离屏幕,那么你可以添加一个alpha动画,并使用AnimatorListenerAdapter设置可见性。 动画文档

其他回答

使用这个类:

public class ExpandCollapseExtention {

 public static void expand(View view) {
    view.setVisibility(View.VISIBLE);

    final int widthSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
    final int heightSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
    view.measure(widthSpec, heightSpec);

    ValueAnimator mAnimator = slideAnimator(view, 0, view.getMeasuredHeight());
    mAnimator.start();
}


public static void collapse(final View view) {
    int finalHeight = view.getHeight();

    ValueAnimator mAnimator = slideAnimator(view, finalHeight, 0);

    mAnimator.addListener(new Animator.AnimatorListener() {

        @Override
        public void onAnimationEnd(Animator animator) {               
            view.setVisibility(View.GONE);
        }


        @Override
        public void onAnimationStart(Animator animation) {

        }


        @Override
        public void onAnimationCancel(Animator animation) {

        }


        @Override
        public void onAnimationRepeat(Animator animation) {

        }
    });
    mAnimator.start();
}


private static ValueAnimator slideAnimator(final View v, int start, int end) {

    ValueAnimator animator = ValueAnimator.ofInt(start, end);

    animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {

        @Override
        public void onAnimationUpdate(ValueAnimator valueAnimator) {

            int value = (Integer) valueAnimator.getAnimatedValue();
            ViewGroup.LayoutParams layoutParams = v.getLayoutParams();
            layoutParams.height = value;
            v.setLayoutParams(layoutParams);
        }
    });
    return animator;
}
}

科特林

根据Suragch的回答,下面是一种使用View扩展的优雅方式:

fun View.slideUp(duration: Int = 500) {
    visibility = View.VISIBLE
    val animate = TranslateAnimation(0f, 0f, this.height.toFloat(), 0f)
    animate.duration = duration.toLong()
    animate.fillAfter = true
    this.startAnimation(animate)
}

fun View.slideDown(duration: Int = 500) {
    visibility = View.VISIBLE
    val animate = TranslateAnimation(0f, 0f, 0f, this.height.toFloat())
    animate.duration = duration.toLong()
    animate.fillAfter = true
    this.startAnimation(animate)
}

然后无论你想在哪里使用它,你只需要myview。slideup()或myview。slidedown ()

Suragch用科特林语回答。这对我很管用。

class MainActivity : AppCompatActivity() {

var isUp: Boolean = false

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)

    var myView: View = findViewById(R.id.my_view)
    var myButton: Button = findViewById(R.id.my_button)

    //Initialize as invisible
    myView.visibility = View.INVISIBLE
    myButton.setText("Slide up")

    isUp = false

}


fun View.slideUp(duration: Int = 500){
    visibility = View.VISIBLE
    val animate = TranslateAnimation(0f, 0f, this.height.toFloat(), 0f)
    animate.duration = duration.toLong()
    animate.fillAfter = true
    this.startAnimation(animate)
}

fun View.slideDown(duration: Int = 500) {
    visibility = View.VISIBLE
    val animate = TranslateAnimation(0f, 0f, 0f, this.height.toFloat())
    animate.duration = duration.toLong()
    animate.fillAfter = true
    this.startAnimation(animate)
}

fun onSlideViewButtonClick(view: View){
    if(isUp){
        my_view.slideDown()
        my_button.setText("Slide Up")

    }
    else{
        my_view.slideUp()
        my_button.setText("Slide Down")
    }
    isUp = !isUp
}

}

最简单的解决方案:在持有视图的容器上设置android:animateLayoutChanges="true"。

如果你有一个如下所示的布局,这个容器中所有视图的可见性变化都将自动动画化。

<LinearLayout android:id="@+id/container"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:animateLayoutChanges="true"
    >

    <Views_which_change_visibility>

</LinearLayout>

你可以在动画布局变化- Android开发者上找到更多细节

如果你想同时显示/隐藏多个视图,你可以使用TransitionSet(因为你不能同时播放2个“单个”过渡)

fun slideTopBottomVisibility(topLayout: View, bottomLayout: View, show: Boolean) {
    val topTransition: Transition = Slide(Gravity.TOP)
    topTransition.duration = 600
    topTransition.addTarget(topLayout)

    val bottomTransition: Transition = Slide(Gravity.BOTTOM)
    bottomTransition.duration = 600
    bottomTransition.addTarget(bottomLayout)

    val transitionSet = TransitionSet()
    transitionSet.addTransition(topTransition)
    transitionSet.addTransition(bottomTransition)

    TransitionManager.beginDelayedTransition(topLayout.parent as ViewGroup, transitionSet)
    topLayout.visibility = if (show) View.VISIBLE else View.GONE
    bottomLayout.visibility = if (show) View.VISIBLE else View.GONE
}