显示跳转

        Intent ite = new Intent();    
        ite.putExtra("acount", et.getText().toString());
        ite.setClass(this, MainActivity_two.class);
        startActivity(ite);

隐示跳转

    Intent ite = new Intent();
        ite.putExtra("acount", et.getText().toString());
    
        ite.setAction("com.example.intenta_b.MainActivity_two_twoavc");
        ite.addCategory("android.intent.category.DEFAULT");

        startActivity(ite);

// 这里的参数值activity的设置category默认是default是手机平板等

 <activity
            android:name="com.example.intenta_b.MainActivity_two"
            android:label="@string/title_activity_main_activity_two" >
            <intent-filter>
                <action android:name="com.example.intenta_b.MainActivity_two_twoavc" />
                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter>
        </activity>

打电话

          Intent call = new Intent();
        call.setAction(Intent.ACTION_CALL);
        call.setData(Uri.parse("tel://110"));
        startActivity(call);

如果传入的参数是对象的话：

public <T extends Parcelable> T getParcelableExtra(String name)