CollapsingToolbarLayoutActivity.java

package com.ximsfei.skindemo;

import android.os.Bundle;
import android.support.design.widget.AppBarLayout;
import android.support.design.widget.CollapsingToolbarLayout;
import android.support.v7.widget.Toolbar;
import android.text.TextUtils;
import android.view.View;
import android.view.animation.AlphaAnimation;
import android.widget.FrameLayout;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;

import skin.support.SkinCompatManager;
import skin.support.utils.SkinPreference;

/**
 * Created by ximsfei on 17-3-2.
 */

public class CollapsingToolbarLayoutActivity extends BaseActivity {

    // 控制ToolBar的变量
    private static final float PERCENTAGE_TO_SHOW_TITLE_AT_TOOLBAR = 0.9f;
    private static final float PERCENTAGE_TO_HIDE_TITLE_DETAILS = 0.3f;

    private static final int ALPHA_ANIMATIONS_DURATION = 200;

    private boolean mIsTheTitleVisible = false;
    private boolean mIsTheTitleContainerVisible = true;

    ImageView mIvPlaceholder; // 大图片

    LinearLayout mLlTitleContainer; // Title的LinearLayout

    FrameLayout mFlTitleContainer; // Title的FrameLayout

    AppBarLayout mAblAppBar; // 整个可以滑动的AppBar

    TextView mTvToolbarTitle; // 标题栏Title

    Toolbar mTbToolbar; // 工具栏

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_collapsing_toolbar_layout);
        mIvPlaceholder = (ImageView) findViewById(R.id.main_iv_placeholder);
        mLlTitleContainer = (LinearLayout) findViewById(R.id.main_ll_title_container);
        mFlTitleContainer = (FrameLayout) findViewById(R.id.main_fl_title);
        mAblAppBar = (AppBarLayout) findViewById(R.id.main_abl_app_bar);
        mTvToolbarTitle = (TextView) findViewById(R.id.main_tv_toolbar_title);
        mTbToolbar = (Toolbar) findViewById(R.id.main_tb_toolbar);
        mTbToolbar.setTitle("");

        // AppBar的监听
        mAblAppBar.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
            @Override
            public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
                int maxScroll = appBarLayout.getTotalScrollRange();
                float percentage = (float) Math.abs(verticalOffset) / (float) maxScroll;
                handleAlphaOnTitle(percentage);
                handleToolbarTitleVisibility(percentage);
            }
        });

        findViewById(R.id.small_photo).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (TextUtils.isEmpty(SkinPreference.getInstance().getSkinName())) {
                    SkinCompatManager.getInstance().loadSkin("night.skin", null);
                } else {
                    SkinCompatManager.getInstance().restoreDefaultTheme();
                }
            }
        });

        initParallaxValues(); // 自动滑动效果
    }

    // 设置自动滑动的动画效果
    private void initParallaxValues() {
        CollapsingToolbarLayout.LayoutParams petDetailsLp =
                (CollapsingToolbarLayout.LayoutParams) mIvPlaceholder.getLayoutParams();

        CollapsingToolbarLayout.LayoutParams petBackgroundLp =
                (CollapsingToolbarLayout.LayoutParams) mFlTitleContainer.getLayoutParams();

        petDetailsLp.setParallaxMultiplier(0.9f);
        petBackgroundLp.setParallaxMultiplier(0.3f);

        mIvPlaceholder.setLayoutParams(petDetailsLp);
        mFlTitleContainer.setLayoutParams(petBackgroundLp);
    }

    // 处理ToolBar的显示
    private void handleToolbarTitleVisibility(float percentage) {
        if (percentage >= PERCENTAGE_TO_SHOW_TITLE_AT_TOOLBAR) {
            if (!mIsTheTitleVisible) {
                startAlphaAnimation(mTvToolbarTitle, ALPHA_ANIMATIONS_DURATION, View.VISIBLE);
                mIsTheTitleVisible = true;
            }
        } else {
            if (mIsTheTitleVisible) {
                startAlphaAnimation(mTvToolbarTitle, ALPHA_ANIMATIONS_DURATION, View.INVISIBLE);
                mIsTheTitleVisible = false;
            }
        }
    }

    // 控制Title的显示
    private void handleAlphaOnTitle(float percentage) {
        if (percentage >= PERCENTAGE_TO_HIDE_TITLE_DETAILS) {
            if (mIsTheTitleContainerVisible) {
                startAlphaAnimation(mLlTitleContainer, ALPHA_ANIMATIONS_DURATION, View.INVISIBLE);
                mIsTheTitleContainerVisible = false;
            }
        } else {
            if (!mIsTheTitleContainerVisible) {
                startAlphaAnimation(mLlTitleContainer, ALPHA_ANIMATIONS_DURATION, View.VISIBLE);
                mIsTheTitleContainerVisible = true;
            }
        }
    }

    // 设置渐变的动画
    public static void startAlphaAnimation(View v, long duration, int visibility) {
        AlphaAnimation alphaAnimation = (visibility == View.VISIBLE)
                ? new AlphaAnimation(0f, 1f)
                : new AlphaAnimation(1f, 0f);

        alphaAnimation.setDuration(duration);
        alphaAnimation.setFillAfter(true);
        v.startAnimation(alphaAnimation);
    }

    @Override
    protected boolean skinStatusBarColorEnable() {
        return false;
    }
}