Android开发中的杂⑦杂⑧

1.沉浸式状态栏设置

java代码

if (Build.VERSION.SDK_INT >= 21) {
        View decorView = getWindow().getDecorView();
        int option = View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                | View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION;
        decorView.setSystemUiVisibility(option);
        getWindow().setStatusBarColor(Color.TRANSPARENT);
        getWindow().setNavigationBarColor(Color.TRANSPARENT);//导航栏透明
}

xml

根布局中设置fitsSystemWindows 和background

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/layout_bg"
    android:fitsSystemWindows="true"
    android:orientation="vertical">
    
</LinearLayout>

2.xml渐变色背景设置

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <!-- 渐变色 -->
    <gradient
        android:angle="0"
        android:endColor="#2C364C"
        android:centerColor="#47607C"
        android:startColor="#47607C"
        />

</shape>

3.Activity全屏设置

import android.view.WindowManager;
import android.support.v7.app.ActionBar;

/**
* hide action bar
*/
private void hideActionBar() {
// Hide UI
ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
actionBar.hide();
}
}

/**
* set the activity display in full screen
*/
private void setFullScreen() {
this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
}

4.十六进制和颜色透明度对照关系

100% — FF	90% — E6	80% — CC	70% — B3	60% — 99	50% — 80	40% — 66	30% — 4D	20% — 33	10% — 1A
99% — FC	89% — E3	79% — C9	69% — B0	59% — 96	49% — 7D	39% — 63	29% — 4A	19% — 30	9% — 17
98% — FA	88% — E0	78% — C7	68% — AD	58% — 94	48% — 7A	38% — 61	28% — 47	18% — 2E	8% — 14
97% — F7	87% — DE	77% — C4	67% — AB	57% — 91	47% — 78	37% — 5E	27% — 45	17% — 2B	7% — 12
96% — F5	86% — DB	76% — C2	66% — A8	56% — 8F	46% — 75	36% — 5C	26% — 42	16% — 29	6% — 0F
95% — F2	85% — D9	75% — BF	65% — A6	55% — 8C	45% — 73	35% — 59	25% — 40	15% — 26	5% — 0D
94% — F0	84% — D6	74% — BD	64% — A3	54% — 8A	44% — 70	34% — 57	24% — 3D	14% — 24	4% — 0A
93% — ED	83% — D4	73% — BA	63% — A1	53% — 87	43% — 6E	33% — 54	23% — 3B	13% — 21	3% — 08
92% — EB	82% — D1	72% — B8	62% — 9E	52% — 85	42% — 6B	32% — 52	22% — 38	12% — 1F	2% — 05
91% — E8	81% — CF	71% — B5	61% — 9C	51% — 82	41% — 69	31% — 4F	21% — 36	11% — 1C	1% — 03

5.xml圆角背景+阴影+内容区渐变

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
        <shape android:shape="rectangle">
            <solid android:color="#4D2E364A"/>
            <corners android:radius="5dp"/>
        </shape>
    </item>
    <item android:bottom="2dp"
        android:left="0dp"
        android:right="1dp"
        android:top="0dp">
        <shape android:shape="rectangle">
            <gradient
                android:angle="90"
                android:endColor="#FFFFFF"
                android:startColor="#C4DCF1"
                />
            <corners android:radius="5dp"/>
        </shape>
    </item>
</layer-list>

6.只有边框的xml shape背景图

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <stroke android:width="2dp" android:color="#4591F3"/>
    <corners android:radius="45dp"/>
</shape>

7.xml圆角背景+阴影渐变

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
        <shape android:shape="rectangle">
            <padding
                android:bottom="1dp"
                android:left="1dp"
                android:right="1dp"
                android:top="1dp" />
            <solid android:color="#0DC0C0C9" />
            <corners android:radius="8dp" />
        </shape>
    </item>
    <item>
        <shape android:shape="rectangle">
            <padding
                android:bottom="1dp"
                android:left="1dp"
                android:right="1dp"
                android:top="1dp" />
            <solid android:color="#10C0C0C9" />
            <corners android:radius="8dp" />
        </shape>
    </item>
    <item>
        <shape android:shape="rectangle">
            <padding
                android:bottom="1dp"
                android:left="1dp"
                android:right="1dp"
                android:top="1dp" />
            <solid android:color="#15C0C0C9" />
            <corners android:radius="8dp" />
        </shape>
    </item>
    <item>
        <shape android:shape="rectangle">
            <padding
                android:bottom="1dp"
                android:left="0dp"
                android:right="1dp"
                android:top="0dp" />
            <solid android:color="#20C0C0C9" />
            <corners android:radius="8dp" />
        </shape>
    </item>
    <item>
        <shape android:shape="rectangle">
            <padding
                android:bottom="1dp"
                android:left="0dp"
                android:right="1dp"
                android:top="0dp" />
            <solid android:color="#30C0C0C9" />
            <corners android:radius="8dp" />
        </shape>
    </item>
    <item>
        <shape>
            <solid android:color="#FFFFFF" />
            <corners android:radius="5dp" />
        </shape>
    </item>
</layer-list>

8.TextView文字不居中 文本边距取消留白

添加<TextView>标签属性android:includeFontPadding="false"设置TextView文本边距取消留白

9.xml 去除<Button>自带样式

style="?android:attr/borderlessButtonStyle"

10.xml——虚线画法

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="line">
    <stroke
        android:width="2dp" 
        android:color="#E6F0F8"
        android:dashWidth="3dp"
        android:dashGap="3dp" />
    <size android:height="2dp" />
</shape>

android:width 虚线的宽度
android:dashWidth 虚线一个点点的长度（我也不知道咋描述了）
android:dashGap 虚线点点之间的距离（就这么描述吧）

最后最重要的一步，要在使用改虚线资源的布局里写一句

android:layerType="software"

要不显示出来的效果是一条实心的直线