小常识集锦
1.安排布局的时候不能吧ListView放在 ScrollView里面如：
<ScrollView
android:id="@+id/widget29"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ListView
android:id="@+id/lstView1"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
</ListView>
</ScrollView>
2.通过getIdentifier获得资源
private void showImage() {
String uri = "drawable/icon";
// int imageResource = R.drawable.icon;
int imageResource = getResources().getIdentifier(uri, null, getPackageName());
ImageView imageView = (ImageView) findViewById(R.id.myImageView);
Drawable image = getResources().getDrawable(imageResource);
imageView.setImageDrawable(image);
}
或者String uri = "@drawable/myresource.png";
一般不推荐这样使用 但是不排除变态要求这样。
3. 通过连接打开一个网页
// 当点击一个新 URL
// 默认的 web browser 启动
webView.setWebViewClient(new WebViewClient() {
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
view.loadUrl(url);
return true;
}
});
4.获得手机的信息
mTelephonyMgr = (TelephonyManager)getSystemService(Context.TELEPHONY_SERVICE);
String imei = mTelephonyMgr.getDeviceId();
官方文档：
String getSimCountryIso() : Returns the ISO country code equivalent for the SIM provider's country code.
String getSimOperator() : Returns the MCC+MNC (mobile country code + mobile network code) of the provider of the SIM.
String getSimOperatorName() : Returns the Service Provider Name (SPN).
String getSimSerialNumber() : Returns the serial number of the SIM, if applicable.
int getSimState() : Returns a constant indicating the state of the device SIM card.
String getSubscriberId() : Returns the unique subscriber ID, for example, the IMSI for a GSM phone.
5.程序中加入一个网站
button.setOnClickListener(new OnClickListener() {
public void onClick(View view) {
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse("http://facebook.com"));
startActivity(intent);
}
});
6.隐藏输入法
InputMethodManager imm = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE); imm.hideSoftInputFromWindow(myEditText.getWindowToken(), 0);
7.让button在listview下面 一般用相对布局
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true">
<ListView ...>
<Button android:id="@+id/btnGetMoreResults"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:text="Get more"
android:layout_alignParentBottom="true" />
</RelativeLayout>
8自动发起一个查看图片的设备
Uri uri = Uri.fromFile("/blah/myimage.jpg");
Intent intent = new Intent(android.content.Intent.ACTION_VIEW);
intent.setDataAndType(uri, "image/jpg");
startActivity(intent);
9.toast中自定义一些空间
LayoutInflater inflater = getLayoutInflater();
View layout = inflater.inflate(R.layout.toast_layout, (ViewGroup) findViewById(R.id.toast_layout_root));
TextView text = (TextView) layout.findViewById(R.id.text);
text.setText(content);
image.setImageBitmap(bmImg);
ImageView image = (ImageView) layout.findViewById(R.id.image);
Toast toast = new Toast(getApplicationContext());
toast.setGravity(Gravity.CENTER_VERTICAL, 0, 0);
toast.setDuration(Toast.LENGTH_LONG);
toast.setView(layout);
toast.show();
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/toast_layout_root"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:padding="10dp"
android:background="#DAAA"
>
<ImageView android:id="@+id/image"
android:layout_width="40dp"
android:layout_height="40dp"
android:layout_marginRight="10dp"
/>
<TextView android:id="@+id/text"
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:textColor="#FFF"
/>
</LinearLayout>
10.让背景有个圆角 通常是加一个背景 然后引用：
<?xml version="1.0" encoding="UTF-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<solid android:color="#99FFFFFF"/>
<corners android:radius="30px"/>
<padding android:left="0dp" android:top="0dp" android:right="0dp" android:bottom="0dp" />
</shape>
android:background="@drawable/my_shape_file"