回答編集履歴
1
他の解決方法を追記
answer
CHANGED
@@ -12,4 +12,96 @@
|
|
12
12
|
|
13
13
|
s.Focus();
|
14
14
|
}
|
15
|
+
```
|
16
|
+
|
17
|
+
---
|
18
|
+
ちょっと本格的に、画面が表示されるタイミングでフォーカスを当てる様なエフェクトを作ってみました。
|
19
|
+
|
20
|
+
Androidプロジェクト
|
21
|
+
```C#
|
22
|
+
[assembly: ResolutionGroupName("BlankApp1")]
|
23
|
+
[assembly: ExportEffect(typeof(FocusEffect), nameof(FocusEffect))]
|
24
|
+
namespace BlankApp1.Droid
|
25
|
+
{
|
26
|
+
public class FocusEffect : PlatformEffect
|
27
|
+
{
|
28
|
+
private Listener _listener;
|
29
|
+
|
30
|
+
protected override void OnAttached()
|
31
|
+
{
|
32
|
+
_listener = new Listener(this);
|
33
|
+
Control.ViewTreeObserver.AddOnPreDrawListener(_listener);
|
34
|
+
}
|
35
|
+
|
36
|
+
protected override void OnDetached()
|
37
|
+
{
|
38
|
+
if (_listener != null)
|
39
|
+
{
|
40
|
+
Control.ViewTreeObserver.RemoveOnPreDrawListener(_listener);
|
41
|
+
_listener = null;
|
42
|
+
}
|
43
|
+
}
|
44
|
+
|
45
|
+
private void Focus()
|
46
|
+
{
|
47
|
+
(Element as VisualElement)?.Focus();
|
48
|
+
|
49
|
+
if (_listener != null)
|
50
|
+
{
|
51
|
+
Control.ViewTreeObserver.RemoveOnPreDrawListener(_listener);
|
52
|
+
_listener = null;
|
53
|
+
}
|
54
|
+
}
|
55
|
+
|
56
|
+
private class Listener : Java.Lang.Object, ViewTreeObserver.IOnPreDrawListener
|
57
|
+
{
|
58
|
+
private FocusEffect _effect;
|
59
|
+
|
60
|
+
public Listener(FocusEffect effect)
|
61
|
+
{
|
62
|
+
_effect = effect;
|
63
|
+
}
|
64
|
+
|
65
|
+
public bool OnPreDraw()
|
66
|
+
{
|
67
|
+
_effect.Focus();
|
68
|
+
return true;
|
69
|
+
}
|
70
|
+
}
|
71
|
+
}
|
72
|
+
}
|
73
|
+
```
|
74
|
+
|
75
|
+
共通プロジェクト
|
76
|
+
```C#
|
77
|
+
namespace BlankApp1.Effects
|
78
|
+
{
|
79
|
+
public class FocusEffect : RoutingEffect
|
80
|
+
{
|
81
|
+
public FocusEffect() : base($"BlankApp1.{nameof(FocusEffect)}")
|
82
|
+
{
|
83
|
+
}
|
84
|
+
}
|
85
|
+
}
|
86
|
+
```
|
87
|
+
|
88
|
+
```xml
|
89
|
+
<?xml version="1.0" encoding="utf-8" ?>
|
90
|
+
<ContentPage
|
91
|
+
x:Class="BlankApp1.Views.LoginPage"
|
92
|
+
xmlns="http://xamarin.com/schemas/2014/forms"
|
93
|
+
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
|
94
|
+
xmlns:b="clr-namespace:BlankApp1.Behavior"
|
95
|
+
xmlns:e="clr-namespace:BlankApp1.Effects"
|
96
|
+
xmlns:prism="clr-namespace:Prism.Mvvm;assembly=Prism.Forms"
|
97
|
+
prism:ViewModelLocator.AutowireViewModel="True">
|
98
|
+
|
99
|
+
<StackLayout Style="{StaticResource StackLayoutStyle}">
|
100
|
+
<Entry x:Name="User" >
|
101
|
+
<Entry.Effects>
|
102
|
+
<e:FocusEffect />
|
103
|
+
</Entry.Effects>
|
104
|
+
</Entry>
|
105
|
+
</StackLayout>
|
106
|
+
</ContentPage>
|
15
107
|
```
|