最近在開發中遇到一種個性化的需求，類似於QQ頂部的漸變狀態列的實現，如下圖
首先我們要了解在Android5.0以後，系統API提供直接設定StatusBar來改變狀態列的顏色，然而在4.4上StatusBar變色的基本原理就是將StatusBar本身設定為透明，然後在StatusBar的位置新增一個相同大小的View並上色。沒辦法，我們要做的漸變顏色狀態列就是要相容上下版本的差異
更多關於沉浸式狀態列的瞭解可參考洪洋大神的文章
純色相容狀態列
/**
* 設定狀態列顏色
*
* @param activity 需要設定的activity
* @param color 狀態列顏色值
* @param statusBarAlpha 狀態列透明度
*/
public static void setColor(Activity activity, @ColorInt int color, @IntRange(from = 0, to = 255) int statusBarAlpha) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
//5.0以上版本
//設定FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS屬性才能呼叫setStatusBarColor方法來設定狀態列顏色
activity.getWindow().addFlags(WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS);
//設定FLAG_TRANSLUCENT_STATUS透明狀態列
activity.getWindow().clearFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
//根據輸入的顏色和透明度顯示
activity.getWindow().setStatusBarColor(calculateStatusColor(color, statusBarAlpha));
} else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
//低版本
//新增透明狀態列
activity.getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
//獲取頂級檢視
ViewGroup decorView = (ViewGroup) activity.getWindow().getDecorView();
//獲取頂部的StatusBarView,自定義StatusBarView的Id(在resources中建立Id)
View fakeStatusBarView = decorView.findViewById(R.id.statusbarutil_fake_status_bar_view);
if (fakeStatusBarView != null) {
if (fakeStatusBarView.getVisibility() == View.GONE) {
fakeStatusBarView.setVisibility(View.VISIBLE);
}
//設定頂層顏色
fakeStatusBarView.setBackgroundColor(calculateStatusColor(color, statusBarAlpha));
} else {
//上述不符合，則建立一個View新增到頂級檢視中
decorView.addView(createStatusBarView(activity, color, statusBarAlpha));
}
setRootView(activity);
}
}
複製程式碼calculateStatusColor（計算狀態列顏色）
/**
* 計算狀態列顏色
*
* @param color color值
* @param alpha alpha值
* @return 最終的狀態列顏色
*/
private static int calculateStatusColor(@ColorInt int color, int alpha) {
if (alpha == 0) {
return color;
}
float a = 1 - alpha / 255f;
int red = color >> 16 & 0xff;
int green = color >> 8 & 0xff;
int blue = color & 0xff;
red = (int) (red * a + 0.5);
green = (int) (green * a + 0.5);
blue = (int) (blue * a + 0.5);
return 0xff << 24 | red << 16 | green << 8 | blue;
}
複製程式碼自定義View狀態列
/**
* 自定義View狀態列
*
* @param activity 需要設定的activity
* @param color 狀態列顏色值
* @param alpha 透明值
* @return 狀態列矩形條
*/
private static View createStatusBarView(Activity activity, @ColorInt int color, int alpha) {
// 繪製一個和狀態列一樣高的矩形
View statusBarView = new View(activity);
LinearLayout.LayoutParams params =
new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, getStatusBarHeight(activity));
statusBarView.setLayoutParams(params);
statusBarView.setBackgroundColor(calculateStatusColor(color, alpha));
//自定義的StatusBarView的Id
statusBarView.setId(FAKE_STATUS_BAR_VIEW_ID);
return statusBarView;
}
複製程式碼最後重新規劃佈局
setRootView
/**
* 設定根佈局引數
*/
private static void setRootView(Activity activity) {
//ViewGroup容器存放UI元件
ViewGroup parent = (ViewGroup) activity.findViewById(android.R.id.content);
for (int i = 0, count = parent.getChildCount(); i < count; i++) {
View childView = parent.getChildAt(i);
if (childView instanceof ViewGroup) {
childView.setFitsSystemWindows(true);
((ViewGroup) childView).setClipToPadding(true);
}
}
}
複製程式碼由此純色狀態列的基本配置就可以了，只需要建立Utils工具類在Activity中呼叫即可，
//設定純色狀態列
StatusBarUtil.setColor(this, AppUtils.getColor(R.color.colorPrimary));
複製程式碼漸變色相容狀態列
程式碼如下
/**
* 為介面設定自定義透明View
*
* @param activity 需要設定的activity
* @param statusBarAlpha 狀態列透明度
* @param needOffsetView 需要向下偏移的 View
public static void setTranslucentForWindow(Activity activity, @IntRange(from = 0, to = 255) int statusBarAlpha,
View needOffsetView) {
if (Build.VERSION.SDK_INT > Build.VERSION_CODES.KITKAT) {
//5.0以上版本
setTransparentForWindow(activity);
addTranslucentView(activity, statusBarAlpha);
if (needOffsetView != null) {
Object haveSetOffset = needOffsetView.getTag(TAG_KEY_HAVE_SET_OFFSET);
if (haveSetOffset != null && (Boolean) haveSetOffset) {
return;
}
ViewGroup.MarginLayoutParams layoutParams = (ViewGroup.MarginLayoutParams) needOffsetView.getLayoutParams();
layoutParams.setMargins(layoutParams.leftMargin, layoutParams.topMargin + getStatusBarHeight(activity),
layoutParams.rightMargin, layoutParams.bottomMargin);
needOffsetView.setTag(TAG_KEY_HAVE_SET_OFFSET, true);
}
} else {
//低版本
//新增透明狀態列
activity.getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
//獲取頂級檢視
ViewGroup decorView = (ViewGroup) activity.getWindow().getDecorView();
//獲取頂部的StatusBarView,自定義id
View fakeStatusBarView = decorView.findViewById(FAKE_STATUS_BAR_VIEW_ID);
if (fakeStatusBarView != null) {
if (fakeStatusBarView.getVisibility() == View.GONE) {
fakeStatusBarView.setVisibility(View.VISIBLE);
}
//設定頂層顏色
fakeStatusBarView.setBackgroundResource(R.drawable.shape_gradient);
} else {
//上述不符合，則建立一個View新增到頂級檢視中
View statusBarView = new View(activity);
LinearLayout.LayoutParams params =
new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, getStatusBarHeight(activity));
statusBarView.setLayoutParams(params);
fakeStatusBarView.setBackgroundResource(R.drawable.shape_gradient);
statusBarView.setId(FAKE_STATUS_BAR_VIEW_ID);
decorView.addView(statusBarView);
}
setRootView(activity);
}
}
複製程式碼getStatusBarHeight
/**
* 獲取狀態列高度
*
* @param context context
* @return 狀態列高度
*/
public static int getStatusBarHeight(Context context) {
// 獲得狀態列高度
int resourceId = context.getResources().getIdentifier("status_bar_height", "dimen", "android");
return context.getResources().getDimensionPixelSize(resourceId);
}
複製程式碼setTransparentForWindow
/**
* 設定透明
*/
public static void setTransparentForWindow(Activity activity) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
activity.getWindow().setStatusBarColor(Color.TRANSPARENT);
activity.getWindow()
.getDecorView()
.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
} else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
activity.getWindow()
.setFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS, WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
}
複製程式碼addTranslucentView
/**
* 新增半透明矩形條
*
* @param activity 需要設定的 activity
* @param statusBarAlpha 透明值
*/
private static void addTranslucentView(Activity activity, @IntRange(from = 0, to = 255) int statusBarAlpha) {
ViewGroup contentView = (ViewGroup) activity.findViewById(android.R.id.content);//系統Id
View fakeTranslucentView = contentView.findViewById(FAKE_TRANSLUCENT_VIEW_ID);
if (fakeTranslucentView != null) {
if (fakeTranslucentView.getVisibility() == View.GONE) {
fakeTranslucentView.setVisibility(View.VISIBLE);
}
fakeTranslucentView.setBackgroundColor(Color.argb(statusBarAlpha, 0, 0, 0));
} else {
contentView.addView(createTranslucentStatusBarView(activity, statusBarAlpha));
}
}
複製程式碼由此漸變顏色的狀態列設定，只需要將toolbar作為View傳入，呼叫如下
//設定漸變顏色狀態列
StatusBarUtil.setTransparentForWindow(this, mToolbar);
//佈局如下
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@drawable/shape_gradient"
android:theme="@style/AppTheme.AppBarOverlay"
app:elevation="@dimen/dp0">
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:popupTheme="@style/ToolbarPopupTheme"
app:title="@string/main_toolbar_title_top"
app:titleTextColor="@color/colorPrimary">
</android.support.v7.widget.Toolbar>
</android.support.design.widget.AppBarLayout>
</LinearLayout>
複製程式碼至此，漸變色狀態列的配置已經介紹完全了