Android中有时需动态设置控件四周的drawble图片,这个时候就需要调用 setCompoundDrawables(left, top, right, bottom),四个参数类型都是drawable
Button继承TextView,所以可以采用相同的设置方法
方法一.XML方式
<TextView android:id="@+id/bookTitle" android:layout_width="match_parent" android:layout_height="wrap_content" android:drawableLeft="@drawable/checkmark" android:drawableRight="@drawable/checkmark" android:drawableTop="@drawable/checkmark" android:gravity="center_vertical" android:textStyle="bold" android:textSize="20dip" android:maxLines="1" android:ellipsize="end"/>
方法二.JAVA代码
Drawable img_on, img_off; Resources res = getResources(); img_off = res.getDrawable(R.drawable.btn_strip_mark_off); //调用setCompoundDrawables时,必须调用Drawable.setBounds()方法,否则图片不显示 img_off.setBounds(0, 0, img_off.getMinimumWidth(), img_off.getMinimumHeight()); btn.setCompoundDrawables(img_off, null, null, null); //设置左图标
android 如何设置背景的透明度
半透明<Button android:background="#e0000000" ... /> 透明<Button android:background="#00000000" ... />
颜色和不透明度 (alpha) 值以十六进制表示法表示。任何一种颜色的值范围都是 0 到 255(00 到 ff)。对于 alpha,00 表示完全透明,ff 表示完全不透明。表达式顺序是“aabbggrr”,其中aa=alpha(00 到 ff);bb=blue(00 到 ff);gg=green(00 到 ff);rr=red(00 到 ff)。例如,如果您希望对某叠加层应用不透明度为 50% 的蓝色,则应指定以下值:7fff0000
Java代码
View v = findViewById(R.id.content);//找到你要设透明背景的layout 的id v.getBackground().setAlpha(100);//0~255透明度值 ,0为完全透明,255为不透明
package com.txlong; import android.app.Activity; import android.graphics.Color; import android.os.Bundle; import android.widget.TextView; public class ListViewDemoActivity extends Activity { // private ListView listView; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); TextView tv = new TextView(this); tv.setText("Test set TextView's color."); //方案一:通过ARGB值的方式 /** * set the TextView color as the 0~255's ARGB,These component values * should be [0..255], but there is no range check performed, so if they * are out of range, the returned color is undefined */ // tv.setTextColor(Color.rgb(255, 255, 255)); /** * set the TextView color as the #RRGGBB #AARRGGBB 'red', 'blue', * 'green', 'black', 'white', 'gray', 'cyan', 'magenta', 'yellow', * 'lightgray', 'darkgray' */ tv.setTextColor(Color.parseColor("#FFFFFF")); /** 原来不知道有上边的方法,就用这个笨笨方法了 */ // String StrColor = null; // StrColor = "FFFFFFFF"; // int length = StrColor.length(); // if (length == 6) { // tv.setTextColor(Color.rgb( // Integer.valueOf(StrColor.substring(0, 2), 16), // Integer.valueOf(StrColor.substring(2, 4), 16), // Integer.valueOf(StrColor.substring(4, 6), 16))); // } else if (length == 8) { // tv.setTextColor(Color.argb( // Integer.valueOf(StrColor.substring(0, 2), 16), // Integer.valueOf(StrColor.substring(2, 4), 16), // Integer.valueOf(StrColor.substring(4, 6), 16), // Integer.valueOf(StrColor.substring(6, 8), 16))); // } //方案二:通过资源引用 // tv.setTextColor(getResources().getColor(R.color.my_color)); //方案三:通过资源文件写在String.xml中 // Resources resource = (Resources) getBaseContext().getResources(); // ColorStateList csl = (ColorStateList) resource.getColorStateList(R.color.my_color); // if (csl != null) { // tv.setTextColor(csl); // } //方案四:通过xml文件,如/res/text_color.xml // XmlPullParser xrp = getResources().getXml(R.color.text_color); // try { // ColorStateList csl = ColorStateList.createFromXml(getResources(), xrp); // tv.setTextColor(csl); // } catch (Exception e) { // } // listView = new ListView(this); // // Cursor cursor = getContentResolver().query( // Uri.parse("content://contacts/people"), null, null, null, null); // // startManagingCursor(cursor); // // ListAdapter listAdapter = new SimpleCursorAdapter(this, // android.R.layout.simple_expandable_list_item_2, cursor, // new String[] { "name", "name" }, new int[] { // android.R.id.text1, android.R.id.text2 }); // // listView.setAdapter(listAdapter); // setContentView(listView); setContentView(tv); } }
String.xml文件为:
<?xml version="1.0" encoding="utf-8"?> <resources> <string name="hello">Hello World, ListViewDemoActivity!</string> <string name="app_name">ListViewDemo</string> <color name="my_color">#FFFFFF</color> </resources>
/res/color/text_color.xml
<?xml version="1.0" encoding="utf-8"?> <selector xmlns:android="http://schemas.android.com/apk/res/android"> <item android:state_pressed="true" android:color="#FF111111"/> <!-- pressed --> <item android:state_focused="true" android:color="#FF222222"/> <!-- focused --> <item android:state_selected="true" android:color="#FF333333"/> <!-- selected --> <item android:state_active="true" android:color="#FF444444"/> <!-- active --> <item android:state_checkable="true" android:color="#FF555555"/> <!-- checkable --> <item android:state_checked="true" android:color="#FF666666"/> <!-- checked --> <item android:state_enabled="true" android:color="#FF777777"/> <!-- enabled --> <item android:state_window_focused="true" android:color="#FF888888"/> <!-- window_focused --> </selector>