The RuntimeDPIProvider class provides the default mapping of
similar device DPI values into predefined DPI classes.
An Application may have its runtimeDPIProvider property set to a
subclass of RuntimeDPIProvider to override Flex's default mappings.
Overriding Flex's default mappings will cause changes in the Application's
automatic scaling behavior.
Overriding Flex's default mappings is usually only necessary for devices
that incorrectly report their screenDPI and for devices that may scale better
in a different DPI class.
Flex's default mappings are:
160 DPI
<140 DPI
160 DPI
>=140 DPI and <=200 DPI
240 DPI
>=200 DPI and <=280 DPI
320 DPI
>=280 DPI and <=400 DPI
480 DPI
>=400 DPI and <=560 DPI
640 DPI
>=640 DPI
Subclasses of RuntimeDPIProvider should only depend on runtime APIs
and should not depend on any classes specific to the Flex framework except
mx.core.DPIClassification.
[read-only]
Returns the runtime DPI of the current device by mapping its
flash.system.Capabilities.screenDPI to one of several DPI
values in mx.core.DPIClassification.
Returns the runtime DPI of the current device by mapping its
flash.system.Capabilities.screenDPI to one of several DPI
values in mx.core.DPIClassification.
A number of devices can have slightly different DPI values and Flex maps these
into the several DPI classes.
Flex uses this method to calculate the current DPI value when an Application
authored for a specific DPI is adapted to the current one through scaling.
Exceptions:
All non-retina iPads receive 160 DPI
All retina iPads receive 320 DPI
Implementation public function get runtimeDPI():Number
<?xml version="1.0" encoding="utf-8"?>
<!--
Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements. See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to You under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
-->
<s:ViewNavigatorApplication xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
firstView="views.RuntimeDPIProviderAppView"
applicationDPI="160" runtimeDPIProvider="RuntimeDPIProviderExample" >
<fx:Declarations>
<!-- Place non-visual elements (e.g., services, value objects) here -->
</fx:Declarations>
</s:ViewNavigatorApplication>
RuntimeDPIProviderExample.as
////////////////////////////////////////////////////////////////////////////////
//
// Licensed to the Apache Software Foundation (ASF) under one or more
// contributor license agreements. See the NOTICE file distributed with
// this work for additional information regarding copyright ownership.
// The ASF licenses this file to You under the Apache License, Version 2.0
// (the "License"); you may not use this file except in compliance with
// the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
////////////////////////////////////////////////////////////////////////////////
package
{
import flash.system.Capabilities;
import mx.core.DPIClassification;
import mx.core.RuntimeDPIProvider;
public class RuntimeDPIProviderExample extends RuntimeDPIProvider
{
public function RuntimeDPIProviderExample()
{
}
override public function get runtimeDPI():Number
{
// A tablet reporting an incorrect DPI of 240.
if (Capabilities.screenDPI == 240 &&
Capabilities.screenResolutionX == 600 &&
Capabilities.screenResolutionY == 1024)
{
return DPIClassification.DPI_160;
}
return super.runtimeDPI;
}
}
}
RuntimeDPIProviderAppView.mxml
<?xml version="1.0" encoding="utf-8"?>
<!--
Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements. See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to You under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
-->
<s:View xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark" title="HomeView">
<s:layout>
<s:VerticalLayout />
</s:layout>
<s:Button label="Example Button" />
<s:HSlider />
<s:List width="100%" height="100%" borderVisible="true">
<s:ArrayList>
<fx:String>apple</fx:String>
<fx:String>banana</fx:String>
<fx:String>cherry</fx:String>
<fx:String>diagonal</fx:String>
<fx:String>ergonomical</fx:String>
<fx:String>freedom</fx:String>
<fx:String>gorge</fx:String>
<fx:String>house</fx:String>
<fx:String>ice</fx:String>
</s:ArrayList>
</s:List>
</s:View>
Object