android常用控件的使用方法

2022-12-20 14:46:46

引言

xml很强大

TextView

<TextView

        android:id="@+id/text_view"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:gravity="center"

        android:textSize="24sp"

        android:textColor="#00ff00"

        android:text="This is textview"

         />

Button

语法

<!-- textAllCaps避免全部变为大写 -->

    <Button

        android:id="@+id/button"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:gravity="center"

        android:textSize="24sp"

        android:textColor="#00ff00"

        android:text="This is textview"

        android:textAllCaps="false"

         />

添加点击处理

1.第一种

package com.example.diandodo.helloworld;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.util.Log; // 引入可以使用日志

import android.view.View;

import android.widget.Button;

public class HelloWorldActivity extends AppCompatActivity {

    private static final String TAG = "HelloWorldActivity";

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.hello_world_layout);

        Button button = (Button) findViewById(R.id.button);

        button.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                Log.d(TAG,"Click");

            }

        });

    }

}

2.第二种

package com.example.diandodo.helloworld;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.util.Log; // 引入可以使用日志

import android.view.View;

import android.widget.Button;

public class HelloWorldActivity extends AppCompatActivity implements View.OnClickListener{

    private static final String TAG = "HelloWorldActivity";

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.hello_world_layout);

        Button button = (Button) findViewById(R.id.button);

        button.setOnClickListener(this);

    }

    @Override

    public void onClick(View v) {

        switch (v.getId()) {

            case R.id.button:

                Log.d(TAG,"Click");

                break;

        }

    }

}

EditText

允许用户输入和编辑内容

<EditText

        android:id="@+id/edit_text"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:gravity="left"

        android:hint="Type something here"

         />

小案例，点击获取内容

1.布局

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:orientation="vertical"

    android:layout_width="match_parent"

    android:layout_height="match_parent">

    <!-- textAllCaps避免全部变为大写 -->

    <Button

        android:id="@+id/button"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:gravity="center"

        android:text="点击获取"

        android:textAllCaps="false"

        />

    <EditText

        android:id="@+id/edit_text"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:gravity="left"

        android:hint="Type something here"

        android:maxLines="2"

         />

</LinearLayout>

2.业务

package com.example.diandodo.helloworld;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.util.Log; // 引入可以使用日志

import android.view.View;

import android.widget.Button;

import android.widget.EditText;

import android.widget.Toast;

public class HelloWorldActivity extends AppCompatActivity implements View.OnClickListener{

    private static final String TAG = "HelloWorldActivity";

    private EditText editText; // 定义一个全局变量

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.hello_world_layout);

        Button button = (Button) findViewById(R.id.button);

        editText = (EditText) findViewById(R.id.edit_text);

        button.setOnClickListener(this);

    }

    @Override

    public void onClick(View v) {

        switch (v.getId()) {

            case R.id.button:

                String inputText = editText.getText().toString();

                Toast.makeText(HelloWorldActivity.this,inputText,Toast.LENGTH_SHORT).show();

                break;

        }

    }

}

ImageView

图片展示的控件。

图片通常放在以“drawable”开头的目录下。

<ImageView

        android:id="@+id/image_view"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:src="@drawable/img_1"

        />

小案例，点击更改图片

1.布局

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:orientation="vertical"

    android:layout_width="match_parent"

    android:layout_height="match_parent">

    <!-- textAllCaps避免全部变为大写 -->

    <Button

        android:id="@+id/button"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:gravity="center"

        android:text="点击获取"

        android:textAllCaps="false"

        />

    <EditText

        android:id="@+id/edit_text"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:gravity="left"

        android:hint="Type something here"

        android:maxLines="2"

         />

    <Button

        android:id="@+id/button_change_img"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:gravity="center"

        android:text="点击改变图片"

        android:textAllCaps="false"

        />

    <ImageView

        android:id="@+id/image_view"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:src="@drawable/img_1"

        />

</LinearLayout>

2.业务

package com.example.diandodo.helloworld;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.util.Log; // 引入可以使用日志

import android.view.View;

import android.widget.Button;

import android.widget.EditText;

import android.widget.ImageView;

import android.widget.Toast;

public class HelloWorldActivity extends AppCompatActivity implements View.OnClickListener{

    private static final String TAG = "HelloWorldActivity";

    private EditText editText; // 定义一个全局变量

    private ImageView imageView;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.hello_world_layout);

        editText = (EditText) findViewById(R.id.edit_text);

        imageView= (ImageView) findViewById(R.id.image_view);

        Button button = (Button) findViewById(R.id.button);

        Button button_change_img = (Button) findViewById(R.id.button_change_img);

        button.setOnClickListener(this);

        button_change_img.setOnClickListener(this);

    }

    @Override

    public void onClick(View v) {

        switch (v.getId()) {

            case R.id.button:

                String inputText = editText.getText().toString();

                Toast.makeText(HelloWorldActivity.this,inputText,Toast.LENGTH_SHORT).show();

                break;

            case R.id.button_change_img:

                imageView.setImageResource(R.drawable.img_2);

                break;

        }

    }

}

ProgressBar

进度条

<ProgressBar

        android:id="@+id/progress_bar"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        />

小案例，点击隐藏显示进度条

1.布局

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:orientation="vertical"

    android:layout_width="match_parent"

    android:layout_height="match_parent">

    <!-- textAllCaps避免全部变为大写 -->

    <Button

        android:id="@+id/button"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:gravity="center"

        android:text="点击获取"

        android:textAllCaps="false"

        />

    <EditText

        android:id="@+id/edit_text"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:gravity="left"

        android:hint="Type something here"

        android:maxLines="2"

         />

    <Button

        android:id="@+id/button_change_img"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:gravity="center"

        android:text="点击改变图片"

        android:textAllCaps="false"

        />

    <ImageView

        android:id="@+id/image_view"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:src="@drawable/img_1"

        />

    <Button

        android:id="@+id/button_set_view"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:gravity="center"

        android:text="点击显示隐藏"

        android:textAllCaps="false"

        />

    <ProgressBar

        android:id="@+id/progress_bar"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        />

</LinearLayout>

2.业务

package com.example.diandodo.helloworld;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.util.Log; // 引入可以使用日志

import android.view.View;

import android.widget.Button;

import android.widget.EditText;

import android.widget.ImageView;

import android.widget.ProgressBar;

import android.widget.Toast;

public class HelloWorldActivity extends AppCompatActivity implements View.OnClickListener{

    private static final String TAG = "HelloWorldActivity";

    private EditText editText; // 定义一个全局变量

    private ImageView imageView;

    private ProgressBar progressBar;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.hello_world_layout);

        editText = (EditText) findViewById(R.id.edit_text);

        imageView= (ImageView) findViewById(R.id.image_view);

        progressBar = (ProgressBar) findViewById(R.id.progress_bar);

        Button button = (Button) findViewById(R.id.button);

        Button button_change_img = (Button) findViewById(R.id.button_change_img);

        Button button_set_view = (Button) findViewById(R.id.button_set_view);

        button.setOnClickListener(this);

        button_change_img.setOnClickListener(this);

        button_set_view.setOnClickListener(this);

    }

    @Override

    public void onClick(View v) {

        switch (v.getId()) {

            case R.id.button:

                String inputText = editText.getText().toString();

                Toast.makeText(HelloWorldActivity.this,inputText,Toast.LENGTH_SHORT).show();

                break;

            case R.id.button_change_img:

                imageView.setImageResource(R.drawable.img_2);

                break;

            case R.id.button_set_view:

                if (progressBar.getVisibility() == View.GONE) {

                    progressBar.setVisibility(View.VISIBLE); // INVISIBLE

                } else {

                    progressBar.setVisibility(View.GONE);

                }

                break;

        }

    }

}

设为长的进度条

1.布局调整

<ProgressBar

        android:id="@+id/progress_bar"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:max="100"

        style="?android:attr/progressBarStyleHorizontal"

        />

2.业务处理

@Override

    public void onClick(View v) {

        switch (v.getId()) {

            case R.id.button:

                String inputText = editText.getText().toString();

                Toast.makeText(HelloWorldActivity.this,inputText,Toast.LENGTH_SHORT).show();

                break;

            case R.id.button_change_img:

                imageView.setImageResource(R.drawable.img_2);

                break;

            case R.id.button_set_view:

//                if (progressBar.getVisibility() == View.GONE) {

//                    progressBar.setVisibility(View.VISIBLE); // INVISIBLE

//                } else {

//                    progressBar.setVisibility(View.GONE);

//                }

                int progress = progressBar.getProgress();

                progress = progress + 10;

                progressBar.setProgress(progress);

                break;

        }

    }

这样每次点击，都会增加进度。

AlertDialog

弹出对话框，置顶于所有界面元素之上。

			AlertDialog.Builder dialog = new AlertDialog.Builder(HelloWorldActivity.this);

                dialog.setTitle("这是Dialog");

                dialog.setMessage("一些重要的事情");

                dialog.setCancelable(false);

                dialog.setPositiveButton("OK", new DialogInterface.OnClickListener() {

                    @Override

                    public void onClick(DialogInterface dialog,int which) {

                    }

                });

                dialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {

                    @Override

                    public void onClick(DialogInterface dialog,int which) {

                    }

                });

                dialog.show();

ProgressDialog

会在对话框中显示一个进度条，一般用于表示当前操作比较耗时，让用户耐心等待。

ProgressDialog progressDialog = new ProgressDialog(HelloWorldActivity.this);

                progressDialog.setTitle("这是progressDialog");

                progressDialog.setMessage("Loading...");

                progressDialog.setCancelable(true);

                progressDialog.show();
上一篇：vlc 控件属性和方法


下一篇：Quick Cocos2dx 与 Eclipse 连真机debug遇到的问题