Android - 使用从左向右滑动显示/隐藏TextView

时间:2017-01-13 12:37:09

标签: android view textview show-hide swipe-gesture

我正在尝试显示/隐藏TextView。因此,如果用户从左向右滑动,它将从“橙色渐变视图”后面显示TextView。在显示的文字后,5秒后,它将再次隐藏它,如下图所示:

Swipe left-to-right to show TextView

但我不知道如上所述的最佳实践是什么。 请帮忙。

2 个答案:

答案 0 :(得分:6)

这是xml文件

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        android:id="@+id/activity_theme_sel_ll_main"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

   <!--Add your content here for texview and whatever -->
    </LinearLayout>

现在使用这个类

import android.content.Context;
import android.view.GestureDetector;
import android.view.GestureDetector.SimpleOnGestureListener;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;

/**
 * This TouchListener is Using for very First time ThemeSelection Screen with SwipeLeft Finger
 */
public class OnSwipeTouchListener implements OnTouchListener {

    private final GestureDetector gestureDetector;

    public OnSwipeTouchListener(Context ctx) {
        gestureDetector = new GestureDetector(ctx, new GestureListener());
    }

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        return gestureDetector.onTouchEvent(event);
    }

    private final class GestureListener extends SimpleOnGestureListener {

        private static final int SWIPE_THRESHOLD = 1;
        private static final int SWIPE_VELOCITY_THRESHOLD = 1;

        @Override
        public boolean onDown(MotionEvent e) {
            return true;
        }

        @Override
        public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
            boolean result = false;
            try {
                float diffY = e2.getY() - e1.getY();
                float diffX = e2.getX() - e1.getX();
                if (Math.abs(diffX) > Math.abs(diffY)) {
                    if (Math.abs(diffX) > SWIPE_THRESHOLD && Math.abs(velocityX) > SWIPE_VELOCITY_THRESHOLD) {
                        if (diffX > 0) {
                            onSwipeRight();
                        } else {
                            onSwipeLeft();
                        }
                    }
                    result = true;
                } else if (Math.abs(diffY) > SWIPE_THRESHOLD && Math.abs(velocityY) > SWIPE_VELOCITY_THRESHOLD) {
                    if (diffY > 0) {
                        onSwipeBottom();
                    } else {
                        onSwipeTop();
                    }
                }
                result = true;

            } catch (Exception exception) {
                exception.printStackTrace();
            }
            return result;
        }
    }

    public void onSwipeRight() {
    }

    public void onSwipeLeft() {
    }

    public void onSwipeTop() {
    }

    public void onSwipeBottom() {
    }
}

在您的MainActivity.java类中使用以下代码

//llMain is the root layout of your xml where you want to perform swipe 
        llMain.setOnTouchListener(new OnSwipeTouchListener(ThemeSelectionActivity.this) {
            @Override
            public void onSwipeLeft() {
                super.onSwipeLeft();

                }
            }

            @Override
            public void onSwipeRight() {
                super.onSwipeRight();

    // Put your logic here for text visibility and for timer like progress bar for 5 second and setText 
            }
        });

答案 1 :(得分:1)

在res目录中创建一个目录anim并将其作为slide.xml

<?xml version="1.0" encoding="utf-8"?>
<set
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:interpolator="@android:anim/linear_interpolator"
    android:fillAfter="true">

   <translate
        android:fromXDelta="0%p"
        android:toXDelta="75%p"
        android:duration="800" />
</set>

使用以下方法进行动画

    /**
     * Animate the swipe rightto left
     *
     * @param context context of the activity or fragment
     */
    private void animImage(final Context context) {
        // Load the animation like this
        final Animation animRightToLeft = AnimationUtils.loadAnimation(context, R.anim.anim_move_right_to_left);
        textViewObject.setLayerType(View.LAYER_TYPE_HARDWARE, null);
        // Start the animation like this
        textViewObject.startAnimation(animRightToLeft);
    }

// Now on MainActivity 
llMain.setOnTouchListener(new OnSwipeTouchListener(ThemeSelectionActivity.this) {
            @Override
            public void onSwipeLeft() {
                super.onSwipeLeft();

                }
            }

            @Override
            public void onSwipeRight() {
                super.onSwipeRight();
animImage(getApplicationContext());
            }
        });