1 /*
2  * Copyright (C) 2013 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.documentsui.dirlist;
18 
19 import android.annotation.IntDef;
20 import android.app.FragmentTransaction;
21 import android.content.Context;
22 import android.os.Bundle;
23 import android.util.AttributeSet;
24 import android.widget.LinearLayout;
25 
26 import com.android.documentsui.R;
27 import com.android.documentsui.Shared;
28 
29 import java.lang.annotation.Retention;
30 import java.lang.annotation.RetentionPolicy;
31 
32 /**
33  * This class exists solely to support animated transition of our directory fragment.
34  * The structure of this class is tightly coupled with the static animations defined in
35  * res/animator, specifically the "position" property referenced by
36  * res/animator/dir_{enter,leave}.xml.
37  */
38 public class AnimationView extends LinearLayout {
39 
40     @IntDef(flag = true, value = {
41             ANIM_NONE,
42             ANIM_SIDE,
43             ANIM_LEAVE,
44             ANIM_ENTER
45     })
46     @Retention(RetentionPolicy.SOURCE)
47     public @interface AnimationType {}
48     public static final int ANIM_NONE = 1;
49     public static final int ANIM_SIDE = 2;
50     public static final int ANIM_LEAVE = 3;
51     public static final int ANIM_ENTER = 4;
52 
53     private float mPosition = 0f;
54 
55     // The distance the animation will cover...currently matches the height of the
56     // content area.
57     private int mSpan;
58 
AnimationView(Context context)59     public AnimationView(Context context) {
60         super(context);
61     }
62 
AnimationView(Context context, AttributeSet attrs)63     public AnimationView(Context context, AttributeSet attrs) {
64         super(context, attrs);
65     }
66 
67     @Override
onSizeChanged(int w, int h, int oldw, int oldh)68     protected void onSizeChanged(int w, int h, int oldw, int oldh) {
69         super.onSizeChanged(w, h, oldw, oldh);
70         mSpan = h;
71         setPosition(mPosition);
72     }
73 
getPosition()74     public float getPosition() {
75         return mPosition;
76     }
77 
setPosition(float position)78     public void setPosition(float position) {
79         mPosition = position;
80         // Warning! If we ever decide to switch this to setX (slide left/right)
81         // please remember to add RLT variations of the animations under res/animator-ldrtl.
82         setY((mSpan > 0) ? (mPosition * mSpan) : 0);
83 
84         if (mPosition != 0) {
85             setTranslationZ(getResources().getDimensionPixelSize(R.dimen.dir_elevation));
86         } else {
87             setTranslationZ(0);
88         }
89     }
90 
91     /**
92      * Configures custom animations on the transaction according to the specified
93      * @AnimationType.
94      */
setupAnimations( FragmentTransaction ft, @AnimationType int anim, Bundle args)95     static void setupAnimations(
96             FragmentTransaction ft, @AnimationType int anim, Bundle args) {
97         switch (anim) {
98             case AnimationView.ANIM_SIDE:
99                 args.putBoolean(Shared.EXTRA_IGNORE_STATE, true);
100                 break;
101             case AnimationView.ANIM_ENTER:
102                 // TODO: Document which behavior is being tailored
103                 //     by passing this bit. Remove if possible.
104                 args.putBoolean(Shared.EXTRA_IGNORE_STATE, true);
105                 ft.setCustomAnimations(R.animator.dir_enter, R.animator.fade_out);
106                 break;
107             case AnimationView.ANIM_LEAVE:
108                 ft.setCustomAnimations(R.animator.fade_in, R.animator.dir_leave);
109                 break;
110         }
111     }
112 }
113