Android学习笔记

前言

以下收藏一些Android学习过程中比较有用东西

文章链接

ANDROID SUPPORT兼容包详解
android基础–tools:context=”.MainActivity”作用

1.线性布局设置分割线：

首先给出分割线的样式，也可以使一个图片文件，这里我们用shape

<?xml version="1.0" encoding="utf-8"?><shape xmlns:android="http://schemas.android.com/apk/res/android"    >    <size android:height="2px"/>    <solid android:color="@android:color/holo_orange_dark"/></shape>

然后在线性布局中设置

 android:divider="@drawable/divider_line" //显示位置    android:showDividers="middle"    //距离两边的间距    android:dividerPadding="10px"

2.GridLayout的使用

 <GridLayout        android:layout_width="wrap_content"        android:layout_height="wrap_content"        //设置几行        android:rowCount="2"        //设置几列        android:columnCount="4"        android:orientation="horizontal"        >        <Button            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:text="你好"            //跨几行            android:layout_rowSpan="2"            //必须设置            android:layout_gravity="fill"            />        <Button            android:text="Button"            />        <Button            android:text="你好"            />        <Button            android:text="Button"            />        <Button            android:text="你好"            />        <Button            android:text="Button"            />    </GridLayout>

3.带阴影的文字

android:shadowDx="10"        android:shadowDy="10"        android:shadowColor="#00ff00"        android:shadowRadius="3"

4.带边框的文字

  <TextView        android:layout_width="200dp"        android:layout_height="50dp"        android:text="我是文字"        android:gravity="center"        android:textSize="20sp"        android:background="@drawable/divider_line"        android:textColor="@android:color/white"        />    <TextView        android:layout_width="200dp"        android:layout_height="50dp"        android:layout_marginTop="10dp"        android:text="我是文字"        android:gravity="center"        android:textSize="20sp"        android:background="@drawable/divider_line2"        android:textColor="@android:color/holo_blue_bright"        />

<?xml version="1.0" encoding="utf-8"?><shape xmlns:android="http://schemas.android.com/apk/res/android"    >    <stroke android:color="@android:color/black"            android:width="3px"        />    <corners android:radius="5dp"/>    <solid android:color="@android:color/holo_orange_dark"/></shape>

<?xml version="1.0" encoding="utf-8"?><shape xmlns:android="http://schemas.android.com/apk/res/android"    >    <stroke android:color="@android:color/black"            android:width="3px"        />    <corners android:radius="5dp"/>    <gradient android:angle="90"        android:startColor="@android:color/white"        android:endColor="@android:color/transparent"        /></shape>

gradient设置渐变，angle设置从哪里开始渐变，0代表左边，然后逆时针，依次是90，180，270，下，右，上

5.设置文字周围图片大小

 //获取图片资源数组        Drawable[] drawables = tv.getCompoundDrawables();        //设置上方图片大小，方向为左上右下，索引依次从0-3        drawables[1].setBounds(0,0,200,200);        tv.setCompoundDrawables(drawables[0],drawables[1],drawables[2],drawables[3]);

6.文字设置autoLink

 <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="电话号码：[phone]"        android:autoLink="phone"        android:textSize="20sp"        />    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="邮箱：[e-mail]"        android:autoLink="email"        android:textSize="20sp"        />    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="百度：http://www.baidu.com"        android:autoLink="web"        android:textSize="20sp"        />    <TextView        android:id="@+id/tv"        android:layout_width="wrap_content"        android:layout_height="wrap_content" />

Java代码设置

 tv.setText("中国电信:13399898832");//        设置autoLink类型        tv.setAutoLinkMask(Linkify.PHONE_NUMBERS);//        设置textview的行动方式        tv.setMovementMethod(LinkMovementMethod.getInstance());

设置文字滚动

 <TextView        android:id="@+id/tv"        android:layout_width="200dp"        android:layout_height="30dp"        android:text="大幅扩大数据库法律进行产能，阿斯蒂芬就是快点放假打三分斯蒂芬斯蒂芬地方"        android:textSize="20sp"        android:scrollbars="none"        />

 tv = (TextView) findViewById(R.id.tv);        tv.setMovementMethod(ScrollingMovementMethod.getInstance());

7.TextView与html结合使用
常用的标签：

<font>：设置颜色和字体。<big>：设置字体大号<small>：设置字体小号<i><b>：斜体粗体<a>：连接网址<img>：图片

  String str = "<font color='blue'>百度一下,你就知道<font><br/>";        str += "<a href='http://www.baidu.com'>百度一下<i>adsf</i></a>";        tv.setText(Html.fromHtml(str));        tv.setMovementMethod(LinkMovementMethod.getInstance());

插入图片

    tv = (TextView) findViewById(R.id.tv);       String str = "图片：<img src='ic_launcher'/>";        tv.setText(Html.fromHtml(str, new Html.ImageGetter() {            @Override            public Drawable getDrawable(String source) {                Drawable drawable = null;                try {                   Field field =  R.drawable.class.getField(source);//                    返回对象中字段的值                   int resourceId =  Integer.parseInt(field.get(null).toString());                    drawable = getResources().getDrawable(resourceId);                    drawable.setBounds(0,0,drawable.getIntrinsicWidth(),drawable.getIntrinsicHeight());                } catch (Exception e) {                    e.printStackTrace();                }                return drawable;            }        },null));

    tv = (TextView) findViewById(R.id.tv);        tv2 = (TextView) findViewById(R.id.tv2);        SpannableString span = new SpannableString("红色打电话斜体删除线绿色下划线图片：");//        文本颜色        span.setSpan(new ForegroundColorSpan(Color.RED),0,2, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);//        文本超链接        span.setSpan(new URLSpan("tel:[phone]"),2,5,Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);//        字体样式        span.setSpan(new StyleSpan(Typeface.BOLD_ITALIC),5,7,Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);        //删除线        span.setSpan(new StrikethroughSpan(),7,10,Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);        span.setSpan(new ForegroundColorSpan(Color.GREEN),10,12,Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);//        下划线        span.setSpan(new UnderlineSpan(),12,15,Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);        //设置图片        Drawable drawable = getResources().getDrawable(R.drawable.ic_launcher);        drawable.setBounds(0,0,drawable.getIntrinsicWidth(),drawable.getIntrinsicHeight());        ImageSpan imageSpan = new ImageSpan(drawable,ImageSpan.ALIGN_BOTTOM);        span.setSpan(imageSpan,17,18,Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);        tv.setText(span);        //========================================================其他span        String str = "公共条款";        SpannableString spannableString = new SpannableString(str);        spannableString.setSpan(new ClickableSpan() {            @Override            public void onClick(View widget) {                Toast.makeText(MainActivity.this,"点击了",Toast.LENGTH_SHORT).show();            }            @Override            public void updateDrawState(TextPaint ds) {                super.updateDrawState(ds);                ds.setColor(Color.BLUE);                ds.setUnderlineText(false);            }        },0,str.length(),0);//        必须设置，否则没点击效果        tv2.setMovementMethod(LinkMovementMethod.getInstance());        tv2.setText(spannableString);//        去掉文字点击后北京高亮        tv2.setHighlightColor(Color.TRANSPARENT);

效果图

   tv = (TextView) findViewById(R.id.tv);        tv2 = (TextView) findViewById(R.id.tv2);        StringBuilder sb = new StringBuilder();        for (int i = 0; i < 10; i++) {            sb.append("好友"+i+ ", ");        }        String likeUsers = sb.substring(0,sb.length()-1);        tv.setMovementMethod(LinkMovementMethod.getInstance());        //添加图片        Drawable drawable = getResources().getDrawable(R.drawable.ic_launcher);        drawable.setBounds(0,0,drawable.getIntrinsicWidth(),drawable.getIntrinsicHeight());        ImageSpan imagespan = new ImageSpan(drawable);        SpannableString span = new SpannableString(" ");        span.setSpan(imagespan,0,1, Spanned.SPAN_INCLUSIVE_EXCLUSIVE);        SpannableStringBuilder ssb = new SpannableStringBuilder(span);        //给图片后面添加文字        ssb.append(likeUsers);        String[] result = likeUsers.split(",");        if (result.length > 0) {            for (int i = 0; i < result.length; i++) {                final String name = result[i];                int start = likeUsers.indexOf(name)+span.length();                ssb.setSpan(new ClickableSpan() {                    @Override                    public void onClick(View widget) {                        Toast.makeText(MainActivity.this,name,Toast.LENGTH_SHORT).show();                    }                    @Override                    public void updateDrawState(TextPaint ds) {                        super.updateDrawState(ds);                        ds.setColor(Color.BLUE);                        ds.setUnderlineText(false);                    }                },start,start + name.length(),0);            }            tv.setText(ssb.append("等"+result.length+"人觉得很赞"));            tv.setHighlightColor(Color.TRANSPARENT);        }

设置TextView水平缩放和文字之间的行间距

  <TextView        android:id="@+id/tv"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textSize="20sp"        android:text="我不知道"        android:textScaleX="2"        />    <TextView        android:id="@+id/tv2"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textSize="20sp"        android:text="我不知道\n你好吗"        android:lineSpacingExtra="10dp"        />

设置上下标

    设置上标        SuperscriptSpan superscriptSpan = new SuperscriptSpan();        SpannableString spannableString = new SpannableString("X\"");        spannableString.setSpan(superscriptSpan,1,2, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);        tv.setText(spannableString);//        设置下标        SubscriptSpan subscriptSpan = new SubscriptSpan();        SpannableString spannableString2 = new SpannableString("X1");        spannableString2.setSpan(subscriptSpan,1,2,Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);        tv2.setText(spannableString2);

EditText

//获得焦点后选中所有内容android:selectAllOnFocus="true"

进入页面自动弹出软键盘，只需要两步
1.让edittext获取焦点
2.设置所在Activity

 android:windowSoftInputMode="stateVisible"

setCompoundDrawablesWithIntrinsicBounds
在控件周围设置图片

public class EditTextWithDel extends android.support.v7.widget.AppCompatEditText {    private static final String TAG = "EditTextWithDel";    private Drawable drawable;    public EditTextWithDel(Context context) {        this(context,null);    }    public EditTextWithDel(Context context, AttributeSet attrs) {        super(context, attrs);        init();    }    public void init(){        drawable = getResources().getDrawable(R.drawable.icon_delete);        addTextChangedListener(new TextWatcher() {            @Override            public void beforeTextChanged(CharSequence s, int start, int count, int after) {            }            @Override            public void onTextChanged(CharSequence s, int start, int before, int count) {            }            @Override            public void afterTextChanged(Editable s) {                setDrawable();            }        });        setDrawable();    }    public void setDrawable(){        if(length() < 1) {            setCompoundDrawablesWithIntrinsicBounds(null,null,null,null);        } else {            setCompoundDrawablesWithIntrinsicBounds(null,null, drawable,null);        }    }    @Override    public boolean onTouchEvent(MotionEvent event) {        if(drawable!=null&&event.getAction() == MotionEvent.ACTION_UP) {            int eventX = (int) event.getRawX();            int eventY = (int) event.getRawY();            Log.d(TAG, "onTouchEvent: eventX " + eventX+"eventY"+eventY);            Rect rect = new Rect();//            获取视图在屏幕中的可见坐标            getGlobalVisibleRect(rect);//            设定矩形区域            rect.left = rect.right - 50;            if (rect.contains(eventX,eventY)) {                setText("");            }        }        return super.onTouchEvent(event);    }}

下面以我的魅蓝note3为例，来获取各个部分的尺寸，这里不考虑ActionBar，我们在主题中不使用ActionBar

<!-- Base application theme. -->    <style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">        <!-- Customize your theme here. -->        <item name="colorPrimary">@color/colorPrimary</item>        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>        <item name="colorAccent">@color/colorAccent</item>    </style>

 public void onWindowFocusChanged(boolean hasFocus) {        super.onWindowFocusChanged(hasFocus);        DisplayMetrics displayMetrics = getResources().getDisplayMetrics();        int widthPixels = displayMetrics.widthPixels;        int heightPixels = displayMetrics.heightPixels;        Log.d(TAG, "屏幕宽高: " +widthPixels+":"+heightPixels);        Rect rect = new Rect();        getWindow().getDecorView().getWindowVisibleDisplayFrame(rect);        Log.d(TAG, "引用程序APP区域: "+rect.width()+":"+rect.height());        Rect rect2 = new Rect();        getWindow().getDecorView().getWindowVisibleDisplayFrame(rect2);        int statusBarHeight = rect2.top;        Log.d(TAG, "状态栏高度: "+statusBarHeight);        Rect rect3 = new Rect();        getWindow().findViewById(Window.ID_ANDROID_CONTENT).getDrawingRect(rect3);        Log.d(TAG, "View布局区域: "+rect3.width()+":"+rect3.height());    }

结果如下：