Android Quick Start

Source: Internet
Author: User
Tags command line gettext resource tostring


Project Source Download



Https://github.com/Wang-Jun-Chao/AndroidProjects



Directory structure for Android projects



Activity: The interface that is displayed when the application is opened



SRC: Project Code



R.java: Resource IDs for all resource files in the project



Android.jar:Android jar Package, import this package to use the Android API



Libs: Importing third party jar packages



Assets: Store resource files, such as MP3, video files



Bin: Store the compiled and packaged files



Res: Store resource files, all resource files stored in this folder will generate resource IDs



Drawable: Storing picture resources



Layout: Store the layout file, assign the layout file to the activity through the resource ID, and the interface will show the layout of the layout file definition



Menu: Define style for menus



Strings.xml: Storing string resources, each resource will have a resource ID



Android configuration file (manifest file)



Specify the package name for the application


package="com.itheima.helloworld"


Data/data/com.itheima.helloworld (the package name specified in the code above)



Application generated files are stored under this path



Android's four components need to be configured in the manifest file before use



The configuration is effective for the entire application



The configuration is in effect for the activity



DDMS



Dalvik Debug Monitor Service



Dalvik Debugging and Monitoring service



The common ADB directive



Android Debug Bridge: Android Debugging Bridges



ADB start-server: Start adb process



ADB kill-server: Killing the ADB process



ADB devices: View the device that is currently connected to the development environment, and this command can also start the ADB process



ADB install xxx.apk: Installing APK to Simulator



ADB Uninstall Package Name: Removing the application in the simulator



ADB shell: Go to linux command line



PS: View the running process



LS: View the file structure under the current directory



Netstat-ano: View the process of seizing ports



Phone Dialer



Function: The user enters a number, clicks the call button, starts the system to call the application to dial out the number



1. Define Layout



The component must be set to a wide height, otherwise it cannot be compiled


android:layout_width="wrap_content"
android:layout_height="wrap_content"


If you want to manipulate a component in Java code, the component needs to set the ID so that you can get the component by ID in your code


android:id="@+id/et_phone"


2. Set click on the button to listen



Set the button to listen


// Get the button object by id
Button bt_call = (Button) findViewById (R.id.bt_call);
// Set the button to click
bt_call.setOnClickListener (new MyListener ());


3. Get the number entered by the user


//Get the number entered by the user, first get the input box component
        EditText et_phone = (EditText) findViewById(R.id.et_phone);
        String phone = et_phone.getText().toString();


4. Call the number out.



Android system based on the action mechanism to invoke the application of the system, you tell the system what you want to do, the system will be able to do this action application to you, without this application, will throw the exception



Set the action to inform the system by intent


//Dial out the number
     // First create an intent object
     Intent intent = new Intent ();
     // Set the action and call
     intent.setAction (Intent.ACTION_CALL);
     intent.setData (Uri.parse ("tel:" + phone));
     // tell the system
    startActivity(intent);


Add permissions


<uses-permission android:name="android.permission.CALL_PHONE"/>


Four ways to spell the Click event



First Kind



Define a MyListener implementation Onclicklistener interface


Button bt1 = (Button) findViewById(R.id.bt1);
bt1.setOnClickListener(new MyListener());


Second Kind



Define an anonymous inner class to implement the Onclicklistener interface


Button bt2 = (Button) findViewById(R.id.bt2);
bt2.setOnClickListener(new OnClickListener() {

    @Override
    public void onClick(View v) {
        System.out.println("第二种");

    }
});


Third Kind



Let the current activity implement the Onclicklistener interface


Button bt3 = (Button) findViewById(R.id.bt3);
bt3.setOnClickListener(this);


Fourth Kind



Set the OnClick property to the button node.


android:onClick="click"


Then define a method in the activity with the same name as the property value


public void click(View v){
    System.out.println("第四种");
}


SMS Transmitter



Function: User input number and SMS content, click send button, call SMS API to send SMS to the specified number



1. Define Layout



Tips for entering boxes


android:hint="please input the number"


2. Complete the Click event



Set the OnClick property for the button component first



onclick= "Send"



Define this method in the activity



public void Send (View v) {}



3. Get the number and content entered by the user


EditText et_phone = (EditText) findViewById(R.id.et_phone);
    EditText et_content = (EditText) findViewById(R.id.et_content);
    String phone = et_phone.getText().toString();
    String content = et_content.getText().toString();


4. Invoke API to send SMS


// Call the API for sending SMS
     SmsManager sm = SmsManager.getDefault ();

     //send messages sm.sendTextMessage(phone, null, content, null, null);


* Add Permissions


<uses-permission android:name="android.permission.SEND_SMS"/>


* If the message is too long, you need to split


List<String> smss = sm.divideMessage(content);


More Wonderful content: http://www.bianceng.cnhttp://www.bianceng.cn/OS/extra/


Related Article

Contact Us

The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion; products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the content of the page makes you feel confusing, please write us an email, we will handle the problem within 5 days after receiving your email.

If you find any instances of plagiarism from the community, please send an email to: info-contact@alibabacloud.com and provide relevant evidence. A staff member will contact you within 5 working days.

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

  • Sales Support

    1 on 1 presale consultation

  • After-Sales Support

    24/7 Technical Support 6 Free Tickets per Quarter Faster Response

  • Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.